v3.25.4
Shareholder Report
 12 Months Ended
Dec. 31, 2025
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSR
Amendment Flag false
Registrant Name BlackRock Funds III
Entity Central Index Key 0000893818
Entity Investment Company Type N-1A
Document Period End Date Dec. 31, 2025
C000082487 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2030 Fund
Class Name Class R Shares
Trading Symbol LPRNX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2030 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $99(a) 0.93%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 99 [1]
Expense Ratio, Percent 0.93% [1]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 13.17%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2030 Fund Custom Benchmark returned 14.33%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 13.17 % 5.81 % 7.87 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2030 Fund Custom Benchmark 14.33 5.95 7.94
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2030 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 539,904,136
Holdings Count | Holding 39
Advisory Fees Paid, Amount $ 525,171
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $539,904,136
Number of Portfolio Holdings 39
Net Investment Advisory Fees $525,171
Portfolio Turnover Rate 19%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 55.5 %
Fixed-Income Funds 35.1 %
Money Market Funds 10.1 %
Liabilities in Excess of Other Assets (0.7 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(b)Excludes short-term securities.
C000051481 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2030 Fund
Class Name Class K Shares
Trading Symbol LPSDX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2030 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $25(a) 0.23%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 25 [2]
Expense Ratio, Percent 0.23% [2]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 13.92%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2030 Fund Custom Benchmark returned 14.33%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 13.92 % 6.54 % 8.61 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2030 Fund Custom Benchmark 14.33 5.95 7.94
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2030 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 539,904,136
Holdings Count | Holding 39
Advisory Fees Paid, Amount $ 525,171
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $539,904,136
Number of Portfolio Holdings 39
Net Investment Advisory Fees $525,171
Portfolio Turnover Rate 19%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 55.5 %
Fixed-Income Funds 35.1 %
Money Market Funds 10.1 %
Liabilities in Excess of Other Assets (0.7 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(b)Excludes short-term securities.
C000088835 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2030 Fund
Class Name Investor C Shares
Trading Symbol LPCNX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2030 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $157(a) 1.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 157 [3]
Expense Ratio, Percent 1.48% [3]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 12.51%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2030 Fund Custom Benchmark returned 14.33%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 12.51 % 5.22 % 7.42 %
Investor C Shares (with sales charge) 11.51 5.22 7.42
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2030 Fund Custom Benchmark 14.33 5.95 7.94
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2030 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 539,904,136
Holdings Count | Holding 39
Advisory Fees Paid, Amount $ 525,171
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $539,904,136
Number of Portfolio Holdings 39
Net Investment Advisory Fees $525,171
Portfolio Turnover Rate 19%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 55.5 %
Fixed-Income Funds 35.1 %
Money Market Funds 10.1 %
Liabilities in Excess of Other Assets (0.7 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(b)Excludes short-term securities.
C000011997 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2030 Fund
Class Name Investor A Shares
Trading Symbol LPRDX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2030 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $78(a) 0.73%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 78 [4]
Expense Ratio, Percent 0.73% [4]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 13.27%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2030 Fund Custom Benchmark returned 14.33%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 13.27 % 6.01 % 8.09 %
Investor A Shares (with sales charge) 7.32 4.87 7.51
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2030 Fund Custom Benchmark 14.33 5.95 7.94
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2030 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 539,904,136
Holdings Count | Holding 39
Advisory Fees Paid, Amount $ 525,171
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $539,904,136
Number of Portfolio Holdings 39
Net Investment Advisory Fees $525,171
Portfolio Turnover Rate 19%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 55.5 %
Fixed-Income Funds 35.1 %
Money Market Funds 10.1 %
Liabilities in Excess of Other Assets (0.7 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(b)Excludes short-term securities.
C000011998 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2030 Fund
Class Name Institutional Shares
Trading Symbol STLDX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2030 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $51(a) 0.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 51 [5]
Expense Ratio, Percent 0.48% [5]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 13.60%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2030 Fund Custom Benchmark returned 14.33%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 13.60 % 6.28 % 8.36 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2030 Fund Custom Benchmark 14.33 5.95 7.94
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2030 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2030 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 539,904,136
Holdings Count | Holding 39
Advisory Fees Paid, Amount $ 525,171
Investment Company Portfolio Turnover 19.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $539,904,136
Number of Portfolio Holdings 39
Net Investment Advisory Fees $525,171
Portfolio Turnover Rate 19%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 55.5 %
Fixed-Income Funds 35.1 %
Money Market Funds 10.1 %
Liabilities in Excess of Other Assets (0.7 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 30.4 %
BlackRock Diversified Fixed Income Fund, Class K 23.2 %
International Tilts Master Portfolio 10.0 %
iShares 0-5 Year TIPS Bond ETF 8.2 %
iShares Core MSCI Emerging Markets ETF 5.4 %
BlackRock Tactical Opportunities Fund, Class K 5.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.7 %
iShares Global Infrastructure ETF 1.6 %
iShares MSCI EAFE Small-Cap ETF 1.5 %
BlackRock Real Estate Securities Fund 1.4 %
(b)Excludes short-term securities.
C000012000 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2040 Fund
Class Name Institutional Shares
Trading Symbol STLEX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2040 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $51(a) 0.47%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 51 [6]
Expense Ratio, Percent 0.47% [6]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 16.88%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2040 Fund Custom Benchmark returned 17.67%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 16.88 % 8.84 % 10.26 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2040 Fund Custom Benchmark 17.67 8.48 9.91
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2040 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 561,532,960
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 369,204
Investment Company Portfolio Turnover 16.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $561,532,960
Number of Portfolio Holdings 36
Net Investment Advisory Fees $369,204
Portfolio Turnover Rate 16%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 73.0 %
Fixed-Income Funds 19.8 %
Money Market Funds 10.8 %
Liabilities in Excess of Other Assets (3.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
(b)Excludes short-term securities.
C000011999 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2040 Fund
Class Name Investor A Shares
Trading Symbol LPREX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2040 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $78(a) 0.72%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 78 [7]
Expense Ratio, Percent 0.72% [7]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 16.67%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2040 Fund Custom Benchmark returned 17.67%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 16.67 % 8.59 % 9.99 %
Investor A Shares (with sales charge) 10.55 7.42 9.40
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2040 Fund Custom Benchmark 17.67 8.48 9.91
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2040 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 561,532,960
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 369,204
Investment Company Portfolio Turnover 16.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $561,532,960
Number of Portfolio Holdings 36
Net Investment Advisory Fees $369,204
Portfolio Turnover Rate 16%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 73.0 %
Fixed-Income Funds 19.8 %
Money Market Funds 10.8 %
Liabilities in Excess of Other Assets (3.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
(b)Excludes short-term securities.
C000088838 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2040 Fund
Class Name Investor C Shares
Trading Symbol LPCKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2040 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $159(a) 1.47%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 159 [8]
Expense Ratio, Percent 1.47% [8]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 15.70%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2040 Fund Custom Benchmark returned 17.67%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 15.70 % 7.77 % 9.30 %
Investor C Shares (with sales charge) 14.70 7.77 9.30
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2040 Fund Custom Benchmark 17.67 8.48 9.91
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2040 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 561,532,960
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 369,204
Investment Company Portfolio Turnover 16.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $561,532,960
Number of Portfolio Holdings 36
Net Investment Advisory Fees $369,204
Portfolio Turnover Rate 16%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 73.0 %
Fixed-Income Funds 19.8 %
Money Market Funds 10.8 %
Liabilities in Excess of Other Assets (3.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
(b)Excludes short-term securities.
C000051482 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2040 Fund
Class Name Class K Shares
Trading Symbol LPSFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2040 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $24(a) 0.22%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 24 [9]
Expense Ratio, Percent 0.22% [9]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 17.23%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2040 Fund Custom Benchmark returned 17.67%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 17.23 % 9.13 % 10.51 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2040 Fund Custom Benchmark 17.67 8.48 9.91
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2040 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 561,532,960
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 369,204
Investment Company Portfolio Turnover 16.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $561,532,960
Number of Portfolio Holdings 36
Net Investment Advisory Fees $369,204
Portfolio Turnover Rate 16%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 73.0 %
Fixed-Income Funds 19.8 %
Money Market Funds 10.8 %
Liabilities in Excess of Other Assets (3.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
(b)Excludes short-term securities.
C000082488 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2040 Fund
Class Name Class R Shares
Trading Symbol LPRKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2040 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $100(a) 0.92%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 100 [10]
Expense Ratio, Percent 0.92% [10]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 16.41%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2040 Fund Custom Benchmark returned 17.67%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 16.41 % 8.36 % 9.76 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2040 Fund Custom Benchmark 17.67 8.48 9.91
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2040 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2040 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 561,532,960
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 369,204
Investment Company Portfolio Turnover 16.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $561,532,960
Number of Portfolio Holdings 36
Net Investment Advisory Fees $369,204
Portfolio Turnover Rate 16%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 73.0 %
Fixed-Income Funds 19.8 %
Money Market Funds 10.8 %
Liabilities in Excess of Other Assets (3.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 37.9 %
International Tilts Master Portfolio 15.2 %
BlackRock Diversified Fixed Income Fund, Class K 15.2 %
iShares Core MSCI Emerging Markets ETF 7.6 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.4 %
BlackRock Real Estate Securities Fund 2.9 %
iShares MSCI EAFE Small-Cap ETF 2.2 %
iShares Global Infrastructure ETF 1.9 %
iShares MSCI Canada ETF 0.5 %
(b)Excludes short-term securities.
C000082489 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic Retirement Fund
Class Name Class R Shares
Trading Symbol LPRRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic Retirement Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $97(a) 0.92%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 97 [11]
Expense Ratio, Percent 0.92% [11]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 11.51%.
  • For the same period, the Fund’s benchmark, the Bloomberg U.S. Aggregate Bond Index returned 7.30% and the Russell 1000® Index returned 17.37%. The LifePath Dynamic Retirement Fund Custom Benchmark returned 12.68%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 11.51 % 3.95 % 5.96 %
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
Russell 1000® Index 17.37 13.59 14.59
LifePath Dynamic Retirement Fund Custom Benchmark 12.68 4.13 6.02
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic Retirement Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 502,351,704
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 576,258
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $502,351,704
Number of Portfolio Holdings 36
Net Investment Advisory Fees $576,258
Portfolio Turnover Rate 17%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Fixed-Income Funds 50.1 %
Equity Funds 43.9 %
Money Market Funds 6.5 %
Liabilities in Excess of Other Assets (0.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
(b)Excludes short-term securities.
C000051483 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic Retirement Fund
Class Name Class K Shares
Trading Symbol LPSAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic Retirement Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $23(a) 0.22%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 23 [12]
Expense Ratio, Percent 0.22% [12]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 12.24%.
  • For the same period, the Fund’s benchmark, the Bloomberg U.S. Aggregate Bond Index returned 7.30% and the Russell 1000® Index returned 17.37%. The LifePath Dynamic Retirement Fund Custom Benchmark returned 12.68%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 12.24 % 4.67 % 6.68 %
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
Russell 1000® Index 17.37 13.59 14.59
LifePath Dynamic Retirement Fund Custom Benchmark 12.68 4.13 6.02
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic Retirement Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 502,351,704
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 576,258
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $502,351,704
Number of Portfolio Holdings 36
Net Investment Advisory Fees $576,258
Portfolio Turnover Rate 17%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Fixed-Income Funds 50.1 %
Equity Funds 43.9 %
Money Market Funds 6.5 %
Liabilities in Excess of Other Assets (0.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
(b)Excludes short-term securities.
C000088841 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic Retirement Fund
Class Name Investor C Shares
Trading Symbol LPCRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic Retirement Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $155(a) 1.47%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 155 [13]
Expense Ratio, Percent 1.47% [13]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 10.88%.
  • For the same period, the Fund’s benchmark, the Bloomberg U.S. Aggregate Bond Index returned 7.30% and the Russell 1000® Index returned 17.37%. The LifePath Dynamic Retirement Fund Custom Benchmark returned 12.68%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 10.88 % 3.37 % 5.51 %
Investor C Shares (with sales charge) 9.88 3.37 5.51
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
Russell 1000® Index 17.37 13.59 14.59
LifePath Dynamic Retirement Fund Custom Benchmark 12.68 4.13 6.02
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic Retirement Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 502,351,704
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 576,258
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $502,351,704
Number of Portfolio Holdings 36
Net Investment Advisory Fees $576,258
Portfolio Turnover Rate 17%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Fixed-Income Funds 50.1 %
Equity Funds 43.9 %
Money Market Funds 6.5 %
Liabilities in Excess of Other Assets (0.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
(b)Excludes short-term securities.
C000012001 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic Retirement Fund
Class Name Investor A Shares
Trading Symbol LPRAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic Retirement Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $76(a) 0.72%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 76 [14]
Expense Ratio, Percent 0.72% [14]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 11.74%.
  • For the same period, the Fund’s benchmark, the Bloomberg U.S. Aggregate Bond Index returned 7.30% and the Russell 1000® Index returned 17.37%. The LifePath Dynamic Retirement Fund Custom Benchmark returned 12.68%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 11.74 % 4.14 % 6.16 %
Investor A Shares (with sales charge) 5.87 3.03 5.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
Russell 1000® Index 17.37 13.59 14.59
LifePath Dynamic Retirement Fund Custom Benchmark 12.68 4.13 6.02
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic Retirement Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 502,351,704
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 576,258
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $502,351,704
Number of Portfolio Holdings 36
Net Investment Advisory Fees $576,258
Portfolio Turnover Rate 17%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Fixed-Income Funds 50.1 %
Equity Funds 43.9 %
Money Market Funds 6.5 %
Liabilities in Excess of Other Assets (0.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
(b)Excludes short-term securities.
C000012002 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic Retirement Fund
Class Name Institutional Shares
Trading Symbol STLAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic Retirement Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $50(a) 0.47%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 50 [15]
Expense Ratio, Percent 0.47% [15]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 12.01%.
  • For the same period, the Fund’s benchmark, the Bloomberg U.S. Aggregate Bond Index returned 7.30% and the Russell 1000® Index returned 17.37%. The LifePath Dynamic Retirement Fund Custom Benchmark returned 12.68%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 12.01 % 4.40 % 6.43 %
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
Russell 1000® Index 17.37 13.59 14.59
LifePath Dynamic Retirement Fund Custom Benchmark 12.68 4.13 6.02
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic Retirement Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic Retirement Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 502,351,704
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 576,258
Investment Company Portfolio Turnover 17.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $502,351,704
Number of Portfolio Holdings 36
Net Investment Advisory Fees $576,258
Portfolio Turnover Rate 17%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Fixed-Income Funds 50.1 %
Equity Funds 43.9 %
Money Market Funds 6.5 %
Liabilities in Excess of Other Assets (0.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
BlackRock Diversified Fixed Income Fund, Class K 40.5 %
Diversified Equity Master Portfolio 24.2 %
iShares 0-5 Year TIPS Bond ETF 9.6 %
International Tilts Master Portfolio 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Core MSCI Emerging Markets ETF 3.9 %
iShares Global Infrastructure ETF 1.8 %
iShares MSCI EAFE Small-Cap ETF 1.2 %
BlackRock Real Estate Securities Fund 0.2 %
iShares MSCI Canada ETF 0.2 %
(b)Excludes short-term securities.
C000063261 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2050 Fund
Class Name Institutional Shares
Trading Symbol STLFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2050 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $55(a) 0.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 55 [16]
Expense Ratio, Percent 0.50% [16]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 20.05%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2050 Fund Custom Benchmark returned 20.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 20.05 % 10.38 % 11.23 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2050 Fund Custom Benchmark 20.74 10.41 11.19
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2050 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 425,407,630
Holdings Count | Holding 31
Advisory Fees Paid, Amount $ 307,816
Investment Company Portfolio Turnover 23.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $425,407,630
Number of Portfolio Holdings 31
Net Investment Advisory Fees $307,816
Portfolio Turnover Rate 23%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 86.0 %
Money Market Funds 17.4 %
Fixed-Income Funds 7.0 %
Liabilities in Excess of Other Assets (10.4 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000063260 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2050 Fund
Class Name Investor A Shares
Trading Symbol LPRFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2050 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $82(a) 0.75%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 82 [17]
Expense Ratio, Percent 0.75% [17]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 19.79%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2050 Fund Custom Benchmark returned 20.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 19.79 % 10.11 % 10.95 %
Investor A Shares (with sales charge) 13.50 8.93 10.36
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2050 Fund Custom Benchmark 20.74 10.41 11.19
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2050 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 425,407,630
Holdings Count | Holding 31
Advisory Fees Paid, Amount $ 307,816
Investment Company Portfolio Turnover 23.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $425,407,630
Number of Portfolio Holdings 31
Net Investment Advisory Fees $307,816
Portfolio Turnover Rate 23%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 86.0 %
Money Market Funds 17.4 %
Fixed-Income Funds 7.0 %
Liabilities in Excess of Other Assets (10.4 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000088844 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2050 Fund
Class Name Investor C Shares
Trading Symbol LPCPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2050 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $164(a) 1.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 164 [18]
Expense Ratio, Percent 1.50% [18]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 18.85%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2050 Fund Custom Benchmark returned 20.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 18.85 % 9.29 % 10.26 %
Investor C Shares (with sales charge) 17.85 9.29 10.26
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2050 Fund Custom Benchmark 20.74 10.41 11.19
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2050 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 425,407,630
Holdings Count | Holding 31
Advisory Fees Paid, Amount $ 307,816
Investment Company Portfolio Turnover 23.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $425,407,630
Number of Portfolio Holdings 31
Net Investment Advisory Fees $307,816
Portfolio Turnover Rate 23%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 86.0 %
Money Market Funds 17.4 %
Fixed-Income Funds 7.0 %
Liabilities in Excess of Other Assets (10.4 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000063262 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2050 Fund
Class Name Class K Shares
Trading Symbol LPSGX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2050 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $28(a) 0.25%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 28 [19]
Expense Ratio, Percent 0.25% [19]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 20.37%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2050 Fund Custom Benchmark returned 20.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 20.37 % 10.66 % 11.48 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2050 Fund Custom Benchmark 20.74 10.41 11.19
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2050 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 425,407,630
Holdings Count | Holding 31
Advisory Fees Paid, Amount $ 307,816
Investment Company Portfolio Turnover 23.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $425,407,630
Number of Portfolio Holdings 31
Net Investment Advisory Fees $307,816
Portfolio Turnover Rate 23%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 86.0 %
Money Market Funds 17.4 %
Fixed-Income Funds 7.0 %
Liabilities in Excess of Other Assets (10.4 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000082490 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2050 Fund
Class Name Class R Shares
Trading Symbol LPRPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2050 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $104(a) 0.95%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 104 [20]
Expense Ratio, Percent 0.95% [20]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 19.53%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2050 Fund Custom Benchmark returned 20.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 19.53 % 9.89 % 10.73 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2050 Fund Custom Benchmark 20.74 10.41 11.19
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2050 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2050 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 425,407,630
Holdings Count | Holding 31
Advisory Fees Paid, Amount $ 307,816
Investment Company Portfolio Turnover 23.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $425,407,630
Number of Portfolio Holdings 31
Net Investment Advisory Fees $307,816
Portfolio Turnover Rate 23%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 86.0 %
Money Market Funds 17.4 %
Fixed-Income Funds 7.0 %
Liabilities in Excess of Other Assets (10.4 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 45.0 %
International Tilts Master Portfolio 15.1 %
iShares Core MSCI Emerging Markets ETF 10.2 %
iShares Core MSCI International Developed Markets ETF 6.0 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares Broad USD Investment Grade Corporate Bond ETF 3.6 %
BlackRock Diversified Fixed Income Fund, Class K 3.3 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Real Estate Securities Fund 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089952 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2035 Fund
Class Name Class R Shares
Trading Symbol LPJRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2035 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $100(a) 0.93%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 100 [21]
Expense Ratio, Percent 0.93% [21]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 14.76%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2035 Fund Custom Benchmark returned 16.08%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 14.76 % 6.99 % 8.80 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2035 Fund Custom Benchmark 16.08 7.27 8.97
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2035 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 458,660,348
Holdings Count | Holding 38
Advisory Fees Paid, Amount $ 354,699
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $458,660,348
Number of Portfolio Holdings 38
Net Investment Advisory Fees $354,699
Portfolio Turnover Rate 13%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 65.2 %
Fixed-Income Funds 25.5 %
Money Market Funds 13.8 %
Liabilities in Excess of Other Assets (4.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089956 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2035 Fund
Class Name Class K Shares
Trading Symbol LPJKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2035 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $25(a) 0.23%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 25 [22]
Expense Ratio, Percent 0.23% [22]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 15.57%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2035 Fund Custom Benchmark returned 16.08%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 15.57 % 7.74 % 9.54 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2035 Fund Custom Benchmark 16.08 7.27 8.97
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2035 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 458,660,348
Holdings Count | Holding 38
Advisory Fees Paid, Amount $ 354,699
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $458,660,348
Number of Portfolio Holdings 38
Net Investment Advisory Fees $354,699
Portfolio Turnover Rate 13%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 65.2 %
Fixed-Income Funds 25.5 %
Money Market Funds 13.8 %
Liabilities in Excess of Other Assets (4.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089954 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2035 Fund
Class Name Investor C Shares
Trading Symbol LPJCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2035 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $158(a) 1.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 158 [23]
Expense Ratio, Percent 1.48% [23]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 14.10%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2035 Fund Custom Benchmark returned 16.08%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 14.10 % 6.40 % 8.34 %
Investor C Shares (with sales charge) 13.10 6.40 8.34
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2035 Fund Custom Benchmark 16.08 7.27 8.97
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2035 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 458,660,348
Holdings Count | Holding 38
Advisory Fees Paid, Amount $ 354,699
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $458,660,348
Number of Portfolio Holdings 38
Net Investment Advisory Fees $354,699
Portfolio Turnover Rate 13%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 65.2 %
Fixed-Income Funds 25.5 %
Money Market Funds 13.8 %
Liabilities in Excess of Other Assets (4.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089953 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2035 Fund
Class Name Investor A Shares
Trading Symbol LPJAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2035 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $78(a) 0.73%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 78 [24]
Expense Ratio, Percent 0.73% [24]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 15.04%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2035 Fund Custom Benchmark returned 16.08%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 15.04 % 7.21 % 9.02 %
Investor A Shares (with sales charge) 9.00 6.06 8.43
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2035 Fund Custom Benchmark 16.08 7.27 8.97
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2035 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 458,660,348
Holdings Count | Holding 38
Advisory Fees Paid, Amount $ 354,699
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $458,660,348
Number of Portfolio Holdings 38
Net Investment Advisory Fees $354,699
Portfolio Turnover Rate 13%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 65.2 %
Fixed-Income Funds 25.5 %
Money Market Funds 13.8 %
Liabilities in Excess of Other Assets (4.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089955 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2035 Fund
Class Name Institutional Shares
Trading Symbol LPJIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2035 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $52(a) 0.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 52 [25]
Expense Ratio, Percent 0.48% [25]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 15.28%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2035 Fund Custom Benchmark returned 16.08%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 15.28 % 7.47 % 9.28 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2035 Fund Custom Benchmark 16.08 7.27 8.97
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2035 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2035 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 458,660,348
Holdings Count | Holding 38
Advisory Fees Paid, Amount $ 354,699
Investment Company Portfolio Turnover 13.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $458,660,348
Number of Portfolio Holdings 38
Net Investment Advisory Fees $354,699
Portfolio Turnover Rate 13%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 65.2 %
Fixed-Income Funds 25.5 %
Money Market Funds 13.8 %
Liabilities in Excess of Other Assets (4.5 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 35.3 %
BlackRock Diversified Fixed Income Fund, Class K 20.5 %
International Tilts Master Portfolio 12.3 %
iShares Core MSCI Emerging Markets ETF 6.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.6 %
BlackRock Real Estate Securities Fund 2.0 %
iShares MSCI EAFE Small-Cap ETF 1.9 %
iShares Global Infrastructure ETF 1.7 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089959 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2045 Fund
Class Name Institutional Shares
Trading Symbol LPHIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2045 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $52(a) 0.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 52 [26]
Expense Ratio, Percent 0.48% [26]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 18.47%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2045 Fund Custom Benchmark returned 19.15%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 18.47 % 9.90 % 10.89 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2045 Fund Custom Benchmark 19.15 9.58 10.68
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2045 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 390,804,021
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 250,292
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $390,804,021
Number of Portfolio Holdings 33
Net Investment Advisory Fees $250,292
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 78.4 %
Money Market Funds 16.3 %
Fixed-Income Funds 12.6 %
Liabilities in Excess of Other Assets (7.3 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089957 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2045 Fund
Class Name Investor A Shares
Trading Symbol LPHAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2045 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $80(a) 0.73%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 80 [27]
Expense Ratio, Percent 0.73% [27]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 18.13%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2045 Fund Custom Benchmark returned 19.15%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 18.13 % 9.63 % 10.62 %
Investor A Shares (with sales charge) 11.93 8.45 10.03
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2045 Fund Custom Benchmark 19.15 9.58 10.68
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2045 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 390,804,021
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 250,292
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $390,804,021
Number of Portfolio Holdings 33
Net Investment Advisory Fees $250,292
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 78.4 %
Money Market Funds 16.3 %
Fixed-Income Funds 12.6 %
Liabilities in Excess of Other Assets (7.3 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089958 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2045 Fund
Class Name Investor C Shares
Trading Symbol LPHCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2045 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $161(a) 1.48%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 161 [28]
Expense Ratio, Percent 1.48% [28]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 17.26%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2045 Fund Custom Benchmark returned 19.15%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 17.26 % 8.80 % 9.94 %
Investor C Shares (with sales charge) 16.26 8.80 9.94
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2045 Fund Custom Benchmark 19.15 9.58 10.68
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2045 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 390,804,021
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 250,292
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $390,804,021
Number of Portfolio Holdings 33
Net Investment Advisory Fees $250,292
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 78.4 %
Money Market Funds 16.3 %
Fixed-Income Funds 12.6 %
Liabilities in Excess of Other Assets (7.3 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089960 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2045 Fund
Class Name Class K Shares
Trading Symbol LPHKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2045 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $25(a) 0.23%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 25 [29]
Expense Ratio, Percent 0.23% [29]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 18.70%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2045 Fund Custom Benchmark returned 19.15%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 18.70 % 10.17 % 11.15 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2045 Fund Custom Benchmark 19.15 9.58 10.68
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2045 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 390,804,021
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 250,292
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $390,804,021
Number of Portfolio Holdings 33
Net Investment Advisory Fees $250,292
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 78.4 %
Money Market Funds 16.3 %
Fixed-Income Funds 12.6 %
Liabilities in Excess of Other Assets (7.3 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089961 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2045 Fund
Class Name Class R Shares
Trading Symbol LPHRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2045 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $101(a) 0.93%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 101 [30]
Expense Ratio, Percent 0.93% [30]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 17.87%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2045 Fund Custom Benchmark returned 19.15%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 17.87 % 9.40 % 10.39 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2045 Fund Custom Benchmark 19.15 9.58 10.68
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2045 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2045 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 390,804,021
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 250,292
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $390,804,021
Number of Portfolio Holdings 33
Net Investment Advisory Fees $250,292
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 78.4 %
Money Market Funds 16.3 %
Fixed-Income Funds 12.6 %
Liabilities in Excess of Other Assets (7.3 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 40.3 %
International Tilts Master Portfolio 14.8 %
iShares Core MSCI Emerging Markets ETF 8.9 %
BlackRock Diversified Fixed Income Fund, Class K 8.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares Broad USD Investment Grade Corporate Bond ETF 4.3 %
BlackRock Real Estate Securities Fund 3.3 %
iShares Core MSCI International Developed Markets ETF 3.0 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares MSCI Canada ETF 0.6 %
(b)Excludes short-term securities.
C000089966 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2055 Fund
Class Name Class R Shares
Trading Symbol LPVRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2055 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $106(a) 0.96%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 106 [31]
Expense Ratio, Percent 0.96% [31]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 20.39%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2055 Fund Custom Benchmark returned 21.59%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class R Shares 20.39 % 10.21 % 10.91 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2055 Fund Custom Benchmark 21.59 10.76 11.38
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2055 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 319,348,756
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 240,304
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $319,348,756
Number of Portfolio Holdings 32
Net Investment Advisory Fees $240,304
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 92.2 %
Money Market Funds 12.0 %
Fixed-Income Funds 2.9 %
Liabilities in Excess of Other Assets (7.1 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
(b)Excludes short-term securities.
C000089965 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2055 Fund
Class Name Class K Shares
Trading Symbol LPVKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2055 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $29(a) 0.26%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 29 [32]
Expense Ratio, Percent 0.26% [32]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 21.21%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2055 Fund Custom Benchmark returned 21.59%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Class K Shares 21.21 % 10.99 % 11.68 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2055 Fund Custom Benchmark 21.59 10.76 11.38
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2055 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 319,348,756
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 240,304
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $319,348,756
Number of Portfolio Holdings 32
Net Investment Advisory Fees $240,304
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 92.2 %
Money Market Funds 12.0 %
Fixed-Income Funds 2.9 %
Liabilities in Excess of Other Assets (7.1 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
(b)Excludes short-term securities.
C000089963 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2055 Fund
Class Name Investor C Shares
Trading Symbol LPVCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2055 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $166(a) 1.51%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 166 [33]
Expense Ratio, Percent 1.51% [33]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 19.73%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2055 Fund Custom Benchmark returned 21.59%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor C Shares 19.73 % 9.60 % 10.45 %
Investor C Shares (with sales charge) 18.73 9.60 10.45
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2055 Fund Custom Benchmark 21.59 10.76 11.38
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2055 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 319,348,756
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 240,304
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $319,348,756
Number of Portfolio Holdings 32
Net Investment Advisory Fees $240,304
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 92.2 %
Money Market Funds 12.0 %
Fixed-Income Funds 2.9 %
Liabilities in Excess of Other Assets (7.1 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
(b)Excludes short-term securities.
C000089962 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2055 Fund
Class Name Investor A Shares
Trading Symbol LPVAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2055 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $84(a) 0.76%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 84 [34]
Expense Ratio, Percent 0.76% [34]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 20.58%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2055 Fund Custom Benchmark returned 21.59%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Investor A Shares 20.58 % 10.43 % 11.14 %
Investor A Shares (with sales charge) 14.25 9.25 10.54
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2055 Fund Custom Benchmark 21.59 10.76 11.38
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2055 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 319,348,756
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 240,304
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $319,348,756
Number of Portfolio Holdings 32
Net Investment Advisory Fees $240,304
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 92.2 %
Money Market Funds 12.0 %
Fixed-Income Funds 2.9 %
Liabilities in Excess of Other Assets (7.1 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
(b)Excludes short-term securities.
C000089964 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2055 Fund
Class Name Institutional Shares
Trading Symbol LPVIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2055 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $56(a) 0.51%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 56 [35]
Expense Ratio, Percent 0.51% [35]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 20.92%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2055 Fund Custom Benchmark returned 21.59%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: January 1, 2016 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years 10 Years
Institutional Shares 20.92 % 10.71 % 11.42 %
Russell 1000® Index 17.37 13.59 14.59
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 2.01
LifePath Dynamic 2055 Fund Custom Benchmark 21.59 10.76 11.38
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2055 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2055 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 319,348,756
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 240,304
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $319,348,756
Number of Portfolio Holdings 32
Net Investment Advisory Fees $240,304
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 92.2 %
Money Market Funds 12.0 %
Fixed-Income Funds 2.9 %
Liabilities in Excess of Other Assets (7.1 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.7 %
International Tilts Master Portfolio 15.0 %
iShares Core MSCI Emerging Markets ETF 10.6 %
iShares Core MSCI International Developed Markets ETF 7.4 %
BlackRock Tactical Opportunities Fund, Class K 4.9 %
iShares MSCI EAFE Small-Cap ETF 2.3 %
BlackRock Diversified Fixed Income Fund, Class K 1.5 %
iShares Broad USD Investment Grade Corporate Bond ETF 1.4 %
iShares Russell 2000 ETF 0.8 %
BlackRock Real Estate Securities Fund 0.8 %
(b)Excludes short-term securities.
C000187070 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2060 Fund
Class Name Institutional Shares
Trading Symbol LPDIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2060 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $55(a) 0.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 55 [36]
Expense Ratio, Percent 0.50% [36]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 21.08%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2060 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: May 31, 2017 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Institutional Shares 21.08 % 10.75 % 11.05 %
Russell 1000® Index 17.37 13.59 14.55
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 1.75
LifePath Dynamic 2060 Fund Custom Benchmark 21.74 10.80 11.21
Performance Inception Date May 31, 2017
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2060 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 167,909,187
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 115,348
Investment Company Portfolio Turnover 20.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $167,909,187
Number of Portfolio Holdings 33
Net Investment Advisory Fees $115,348
Portfolio Turnover Rate 20%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 91.6 %
Money Market Funds 11.2 %
Fixed-Income Funds 1.8 %
Liabilities in Excess of Other Assets (4.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
(b)Excludes short-term securities.
C000187068 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2060 Fund
Class Name Investor A Shares
Trading Symbol LPDAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2060 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $83(a) 0.75%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 83 [37]
Expense Ratio, Percent 0.75% [37]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 20.79%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2060 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: May 31, 2017 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Investor A Shares 20.79 % 10.48 % 10.77 %
Investor A Shares (with sales charge) 14.44 9.29 10.07
Russell 1000® Index 17.37 13.59 14.55
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 1.75
LifePath Dynamic 2060 Fund Custom Benchmark 21.74 10.80 11.21
Performance Inception Date May 31, 2017
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2060 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 167,909,187
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 115,348
Investment Company Portfolio Turnover 20.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $167,909,187
Number of Portfolio Holdings 33
Net Investment Advisory Fees $115,348
Portfolio Turnover Rate 20%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 91.6 %
Money Market Funds 11.2 %
Fixed-Income Funds 1.8 %
Liabilities in Excess of Other Assets (4.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
(b)Excludes short-term securities.
C000187069 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2060 Fund
Class Name Investor C Shares
Trading Symbol LPDCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2060 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $166(a) 1.51%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 166 [38]
Expense Ratio, Percent 1.51% [38]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 19.90%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2060 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: May 31, 2017 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Investor C Shares 19.90 % 9.65 % 9.98 %
Investor C Shares (with sales charge) 18.90 9.65 9.98
Russell 1000® Index 17.37 13.59 14.55
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 1.75
LifePath Dynamic 2060 Fund Custom Benchmark 21.74 10.80 11.21
Performance Inception Date May 31, 2017
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2060 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 167,909,187
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 115,348
Investment Company Portfolio Turnover 20.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $167,909,187
Number of Portfolio Holdings 33
Net Investment Advisory Fees $115,348
Portfolio Turnover Rate 20%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 91.6 %
Money Market Funds 11.2 %
Fixed-Income Funds 1.8 %
Liabilities in Excess of Other Assets (4.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
(b)Excludes short-term securities.
C000187072 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2060 Fund
Class Name Class K Shares
Trading Symbol LPDKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2060 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $28(a) 0.25%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 28 [39]
Expense Ratio, Percent 0.25% [39]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 21.41%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2060 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: May 31, 2017 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Class K Shares 21.41 % 11.02 % 11.30 %
Russell 1000® Index 17.37 13.59 14.55
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 1.75
LifePath Dynamic 2060 Fund Custom Benchmark 21.74 10.80 11.21
Performance Inception Date May 31, 2017
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2060 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 167,909,187
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 115,348
Investment Company Portfolio Turnover 20.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $167,909,187
Number of Portfolio Holdings 33
Net Investment Advisory Fees $115,348
Portfolio Turnover Rate 20%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 91.6 %
Money Market Funds 11.2 %
Fixed-Income Funds 1.8 %
Liabilities in Excess of Other Assets (4.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
(b)Excludes short-term securities.
C000187071 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2060 Fund
Class Name Class R Shares
Trading Symbol LPDRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2060 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $105(a) 0.95%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 105 [40]
Expense Ratio, Percent 0.95% [40]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 20.53%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2060 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: May 31, 2017 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Class R Shares 20.53 % 10.25 % 10.54 %
Russell 1000® Index 17.37 13.59 14.55
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 1.75
LifePath Dynamic 2060 Fund Custom Benchmark 21.74 10.80 11.21
Performance Inception Date May 31, 2017
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2060 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2060 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 167,909,187
Holdings Count | Holding 33
Advisory Fees Paid, Amount $ 115,348
Investment Company Portfolio Turnover 20.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $167,909,187
Number of Portfolio Holdings 33
Net Investment Advisory Fees $115,348
Portfolio Turnover Rate 20%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 91.6 %
Money Market Funds 11.2 %
Fixed-Income Funds 1.8 %
Liabilities in Excess of Other Assets (4.6 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 49.0 %
International Tilts Master Portfolio 14.7 %
iShares Core MSCI Emerging Markets ETF 10.0 %
iShares Core MSCI International Developed Markets ETF 7.2 %
BlackRock Tactical Opportunities Fund, Class K 4.8 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.9 %
iShares Russell 2000 ETF 0.9 %
BlackRock Diversified Fixed Income Fund, Class K 0.8 %
(b)Excludes short-term securities.
C000213847 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2065 Fund
Class Name Class R Shares
Trading Symbol LPWRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2065 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $105(a) 0.95%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 105 [41]
Expense Ratio, Percent 0.95% [41]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 20.44%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2065 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: October 30, 2019 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Class R Shares 20.44 % 10.23 % 11.37 %
Russell 1000® Index 17.37 13.59 15.52
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 0.95
LifePath Dynamic 2065 Fund Custom Benchmark 21.74 10.79 12.19
Performance Inception Date Oct. 30, 2019
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2065 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 83,509,512
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 54,038
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $83,509,512
Number of Portfolio Holdings 36
Net Investment Advisory Fees $54,038
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 87.4 %
Money Market Funds 14.8 %
Fixed-Income Funds 1.6 %
Liabilities in Excess of Other Assets (3.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
(b)Excludes short-term securities.
C000213844 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2065 Fund
Class Name Class K Shares
Trading Symbol LPWKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2065 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $28(a) 0.25%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 28 [42]
Expense Ratio, Percent 0.25% [42]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 21.39%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2065 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: October 30, 2019 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Class K Shares 21.39 % 11.01 % 12.15 %
Russell 1000® Index 17.37 13.59 15.52
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 0.95
LifePath Dynamic 2065 Fund Custom Benchmark 21.74 10.79 12.19
Performance Inception Date Oct. 30, 2019
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2065 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 83,509,512
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 54,038
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $83,509,512
Number of Portfolio Holdings 36
Net Investment Advisory Fees $54,038
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 87.4 %
Money Market Funds 14.8 %
Fixed-Income Funds 1.6 %
Liabilities in Excess of Other Assets (3.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
(b)Excludes short-term securities.
C000213843 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2065 Fund
Class Name Investor C Shares
Trading Symbol LPWCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2065 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $166(a) 1.51%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 166 [43]
Expense Ratio, Percent 1.51% [43]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 19.76%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2065 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: October 30, 2019 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Investor C Shares 19.76 % 9.63 % 10.76 %
Investor C Shares (with sales charge) 18.76 9.63 10.76
Russell 1000® Index 17.37 13.59 15.52
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 0.95
LifePath Dynamic 2065 Fund Custom Benchmark 21.74 10.79 12.19
Performance Inception Date Oct. 30, 2019
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2065 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 83,509,512
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 54,038
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $83,509,512
Number of Portfolio Holdings 36
Net Investment Advisory Fees $54,038
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 87.4 %
Money Market Funds 14.8 %
Fixed-Income Funds 1.6 %
Liabilities in Excess of Other Assets (3.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
(b)Excludes short-term securities.
C000213845 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2065 Fund
Class Name Investor A Shares
Trading Symbol LPWAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2065 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $83(a) 0.75%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 83 [44]
Expense Ratio, Percent 0.75% [44]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 20.66%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2065 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: October 30, 2019 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Investor A Shares 20.66 % 10.45 % 11.59 %
Investor A Shares (with sales charge) 14.32 9.26 10.62
Russell 1000® Index 17.37 13.59 15.52
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 0.95
LifePath Dynamic 2065 Fund Custom Benchmark 21.74 10.79 12.19
Performance Inception Date Oct. 30, 2019
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2065 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 83,509,512
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 54,038
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $83,509,512
Number of Portfolio Holdings 36
Net Investment Advisory Fees $54,038
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 87.4 %
Money Market Funds 14.8 %
Fixed-Income Funds 1.6 %
Liabilities in Excess of Other Assets (3.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
(b)Excludes short-term securities.
C000213846 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2065 Fund
Class Name Institutional Shares
Trading Symbol LPWIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2065 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $55(a) 0.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 55 [45]
Expense Ratio, Percent 0.50% [45]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 21.02%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2065 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: October 30, 2019 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year 5 Years Since Fund
Inception
Institutional Shares 21.02 % 10.73 % 11.88 %
Russell 1000® Index 17.37 13.59 15.52
Bloomberg U.S. Aggregate Bond Index 7.30 (0.36 ) 0.95
LifePath Dynamic 2065 Fund Custom Benchmark 21.74 10.79 12.19
Performance Inception Date Oct. 30, 2019
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2065 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2065 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 83,509,512
Holdings Count | Holding 36
Advisory Fees Paid, Amount $ 54,038
Investment Company Portfolio Turnover 21.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $83,509,512
Number of Portfolio Holdings 36
Net Investment Advisory Fees $54,038
Portfolio Turnover Rate 21%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 87.4 %
Money Market Funds 14.8 %
Fixed-Income Funds 1.6 %
Liabilities in Excess of Other Assets (3.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 46.5 %
International Tilts Master Portfolio 14.0 %
iShares Core MSCI Emerging Markets ETF 9.7 %
iShares Core MSCI International Developed Markets ETF 7.0 %
BlackRock Tactical Opportunities Fund, Class K 4.5 %
iShares MSCI Canada ETF 2.3 %
iShares MSCI EAFE Small-Cap ETF 2.1 %
iShares Russell 2000 ETF 1.0 %
iShares Broad USD Investment Grade Corporate Bond ETF 0.8 %
BlackRock Diversified Fixed Income Fund, Class K 0.7 %
(b)Excludes short-term securities.
C000251825 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2070 Fund
Class Name Institutional Shares
Trading Symbol LPYIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2070 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Institutional Shares $55(a) 0.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 55 [46]
Expense Ratio, Percent 0.50% [46]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Institutional Shares returned 20.98%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2070 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: September 24, 2024 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year Since Fund
Inception
Institutional Shares 20.98 % 19.35 %
Russell 1000® Index 17.37 16.36
Bloomberg U.S. Aggregate Bond Index 7.30 2.89
LifePath Dynamic 2070 Fund Custom Benchmark 21.74 16.39
Performance Inception Date Sep. 24, 2024
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2070 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2070 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 6,076,678
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 3,519
Investment Company Portfolio Turnover 41.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $6,076,678
Number of Portfolio Holdings 32
Net Investment Advisory Fees $3,519
Portfolio Turnover Rate 41%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 97.4 %
Money Market Funds 14.1 %
Fixed-Income Funds 1.3 %
Liabilities in Excess of Other Assets (12.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
(b)Excludes short-term securities.
C000251826 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2070 Fund
Class Name Investor A Shares
Trading Symbol LPYAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2070 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor A Shares $83(a) 0.75%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 83 [47]
Expense Ratio, Percent 0.75% [47]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor A Shares returned 20.73%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2070 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: September 24, 2024 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year Since Fund
Inception
Investor A Shares 20.73 % 19.02 %
Investor A Shares (with sales charge) 14.39 12.77
Russell 1000® Index 17.37 16.36
Bloomberg U.S. Aggregate Bond Index 7.30 2.89
LifePath Dynamic 2070 Fund Custom Benchmark 21.74 16.39
Performance Inception Date Sep. 24, 2024
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2070 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2070 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 6,076,678
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 3,519
Investment Company Portfolio Turnover 41.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $6,076,678
Number of Portfolio Holdings 32
Net Investment Advisory Fees $3,519
Portfolio Turnover Rate 41%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 97.4 %
Money Market Funds 14.1 %
Fixed-Income Funds 1.3 %
Liabilities in Excess of Other Assets (12.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
(b)Excludes short-term securities.
C000251827 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2070 Fund
Class Name Investor C Shares
Trading Symbol LPYCX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2070 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Investor C Shares $165(a) 1.50%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 165 [48]
Expense Ratio, Percent 1.50% [48]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Investor C Shares returned 19.84%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2070 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: September 24, 2024 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year Since Fund
Inception
Investor C Shares 19.84 % 17.90 %
Investor C Shares (with sales charge) 18.84 17.90
Russell 1000® Index 17.37 16.36
Bloomberg U.S. Aggregate Bond Index 7.30 2.89
LifePath Dynamic 2070 Fund Custom Benchmark 21.74 16.39
Performance Inception Date Sep. 24, 2024
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2070 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2070 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 6,076,678
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 3,519
Investment Company Portfolio Turnover 41.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $6,076,678
Number of Portfolio Holdings 32
Net Investment Advisory Fees $3,519
Portfolio Turnover Rate 41%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 97.4 %
Money Market Funds 14.1 %
Fixed-Income Funds 1.3 %
Liabilities in Excess of Other Assets (12.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
(b)Excludes short-term securities.
C000251828 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2070 Fund
Class Name Class K Shares
Trading Symbol LPYKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2070 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class K Shares $28(a) 0.25%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 28 [49]
Expense Ratio, Percent 0.25% [49]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class K Shares returned 21.26%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2070 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: September 24, 2024 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year Since Fund
Inception
Class K Shares 21.26 % 19.70 %
Russell 1000® Index 17.37 16.36
Bloomberg U.S. Aggregate Bond Index 7.30 2.89
LifePath Dynamic 2070 Fund Custom Benchmark 21.74 16.39
Performance Inception Date Sep. 24, 2024
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2070 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2070 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 6,076,678
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 3,519
Investment Company Portfolio Turnover 41.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $6,076,678
Number of Portfolio Holdings 32
Net Investment Advisory Fees $3,519
Portfolio Turnover Rate 41%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 97.4 %
Money Market Funds 14.1 %
Fixed-Income Funds 1.3 %
Liabilities in Excess of Other Assets (12.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
(b)Excludes short-term securities.
C000251824 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock LifePath® Dynamic 2070 Fund
Class Name Class R Shares
Trading Symbol LPYRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock LifePath® Dynamic 2070 Fund (the “Fund”) for the period of January 1, 2025 to December 31, 2025.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information about the Fund at blackrock.com/fundreports. You can also request this information by contacting us at (800) 441‑7762.
Additional Information Phone Number (800) 441‑7762
Additional Information Website blackrock.com/fundreports
Expenses [Text Block]
What were the Fund costs for the last year ?
(based on a hypothetical $10,000 investment)
Class name Costs of a $10,000
investment		 Costs paid as a percentage of a
$10,000 investment
Class R Shares $105(a) 0.95%(a)
​(a)
Excludes fees and expenses incurred indirectly as a result of investments in underlying funds.
Expenses Paid, Amount $ 105 [50]
Expense Ratio, Percent 0.95% [50]
Factors Affecting Performance [Text Block]
How did the Fund perform last year ?
  • For the reporting period ended December 31, 2025, the Fund’s Class R Shares returned 20.45%.
  • For the same period, the Fund’s benchmark, the Russell 1000® Index returned 17.37% and the Bloomberg U.S. Aggregate Bond Index returned 7.30%. The LifePath Dynamic 2070 Fund Custom Benchmark returned 21.74%.
What contributed to performance?
U.S. equities were the top contributor to absolute performance in the funds furthest from retirement, followed by international equities, BlackRock Tactical Opportunities Fund (a liquid macro strategy), investment-grade bonds, and U.S. real estate investment trusts (REITs).
U.S. equities were the top contributor in the funds at and near retirement, followed by investment-grade bonds, international equities, U.S. Treasury Inflation Protected Securities (TIPS), global infrastructure stocks, and BlackRock Tactical Opportunities Fund.
The funds used derivatives, including financial futures, swaps, and foreign currency transactions, as a means to hedge and/or take outright views on equities, interest rates, credit risk, and/or currencies. The use of derivatives as opposed to physical securities did not have a material impact on performance.
What detracted from performance?
Currency positioning was the primary detractor from performance in the funds furthest from retirement.
In the vintages at and near retirement, currency pair trades were the primary detractor.
The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions. These views are not intended to be a forecast of future events and are no guarantee of future results.
Performance Past Does Not Indicate Future [Text] Past performance is not an indication of future results.
Line Graph [Table Text Block]
Fund performance
Cumulative performance: September 24, 2024 through December 31, 2025
Initial investment of $10,000
Fund Performance - Growth of 10K
 See “Average annual total returns” for additional information on fund performance.
Average Annual Return [Table Text Block]
Average annual total returns
1 Year Since Fund
Inception
Class R Shares 20.45 % 18.68 %
Russell 1000® Index 17.37 16.36
Bloomberg U.S. Aggregate Bond Index 7.30 2.89
LifePath Dynamic 2070 Fund Custom Benchmark 21.74 16.39
Performance Inception Date Sep. 24, 2024
No Deduction of Taxes [Text Block] Performance results do not reflect the deduction of taxes that a shareholder would pay on fund distributions or on the redemption or sale of fund shares.
Prior Market Index Comparison [Text Block]
The Fund compares its performance to that of a customized weighted index (the “LifePath Dynamic 2070 Fund Custom Benchmark”) comprised of the Bloomberg U.S. Intermediate Credit Bond Index, Bloomberg U.S. Intermediate Government Bond Index, Bloomberg U.S. Long Credit Bond Index, Bloomberg U.S. Long Government Bond Index, Bloomberg U.S. Securitized: MBS, ABS and CMBS Index, FTSE Nareit All Equity REIT Index, ICE® U.S. Treasury 0-5 Year Inflation Linked Bond Index, MSCI ACWI ex USA IMI Index (Net), Russell 1000® Index, Russell 2000® Index and S&P Global Infrastructure IndexTM (Net), which are representative of the asset classes in which the Fund invests. The weightings of the indices in the LifePath Dynamic 2070 Fund Custom Benchmark are adjusted periodically to reflect the investment adviser’s evaluation and adjustment of the Fund’s asset allocation strategy.
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 6,076,678
Holdings Count | Holding 32
Advisory Fees Paid, Amount $ 3,519
Investment Company Portfolio Turnover 41.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $6,076,678
Number of Portfolio Holdings 32
Net Investment Advisory Fees $3,519
Portfolio Turnover Rate 41%
Holdings [Text Block]
What did the Fund invest in?
(as of December 31, 2025)
Portfolio composition
Asset Type(a) Percent of
Net Assets
Equity Funds 97.4 %
Money Market Funds 14.1 %
Fixed-Income Funds 1.3 %
Liabilities in Excess of Other Assets (12.8 )
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
​(a)
The portfolio composition above is calculated using a methodology different than that disclosed in the Fund's prospectus.
​(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Diversified Equity Master Portfolio 50.0 %
International Tilts Master Portfolio 12.8 %
iShares Core MSCI Emerging Markets ETF 11.6 %
iShares Core MSCI International Developed Markets ETF 6.3 %
BlackRock Tactical Opportunities Fund, Class K 4.1 %
iShares Core MSCI EAFE ETF 3.3 %
iShares MSCI Japan ETF 3.0 %
iShares MSCI Canada ETF 2.4 %
iShares MSCI EAFE Small-Cap ETF 1.8 %
iShares Russell 2000 ETF 1.8 %
(b)Excludes short-term securities.
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