v3.26.1
Shareholder Report
12 Months Ended
Jun. 30, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSR
Amendment Flag false
Registrant Name BlackRock Large Cap Focus Value Fund, Inc.
Entity Central Index Key 0000216557
Entity Investment Company Type N-1A
Document Period End Date Jun. 30, 2026
C000006076 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock Large Cap Focus Value Fund, Inc.
Class Name Investor C Shares
Trading Symbol MCBAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock Large Cap Focus Value Fund, Inc. (the “Fund”) for the period of July 1, 2025 to June 30, 2026.
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.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
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 $183 1.63%
Expenses Paid, Amount $ 183
Expense Ratio, Percent 1.63%
Factors Affecting Performance [Text Block]
How did the Fund perform last year?
  • For the reporting period ended June 30, 2026, the Fund's Investor C Shares returned 24.00%.
  • For the same period, the Fund’s benchmark, the Russell 1000 Index returned 22.01% and the Russell 1000 Value Index returned 27.09%.
What contributed to performance?
The largest positive contributor to the Fund’s performance was the allocation to the information technology sector, highlighted by holdings within the technology hardware, storage & peripherals industry. Positioning in both the consumer discretionary and materials sectors also contributed notably, particularly in the automobiles and containers & packaging subsectors, respectively.
What detracted from performance?
The largest detractor from performance was the allocation to the financials sector, where exposure to the financial services industry weighed most heavily on results. While there were no other detractors at the sector level during the period, exposure to the professional services and software industries also detracted from total return.
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: July 1, 2016 through June 30, 2026
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 24.00 % 10.68 % 10.55 %
Investor C Shares (with sales charge) 23.00 10.68 10.55
Russell 1000 Index 22.01 12.66 15.29
Russell 1000 Value Index 27.09 11.17 11.52
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.
Material Change Date Oct. 28, 2025
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 1,997,153,597
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 7,973,483
Investment Company Portfolio Turnover 91.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $1,997,153,597
Number of Portfolio Holdings 52
Net Investment Advisory Fees $7,973,483
Portfolio Turnover Rate 91%
Holdings [Text Block]
What did the Fund invest in?
(as of June 30, 2026)
Sector allocation
Sector(a) Percent of
Net Assets
Information Technology 17.6 %
Financials 17.6 %
Health Care 15.1 %
Industrials 12.9 %
Consumer Discretionary 12.0 %
Consumer Staples 5.6 %
Energy 4.7 %
Utilities 4.0 %
Communication Services 3.9 %
Materials 3.6 %
Real Estate 2.8 %
Short-Term Securities 0.6 %
Liabilities in Excess of Other Assets (0.4 )%
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(a)
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(b)Excludes short-term securities.
Material Fund Change [Text Block]
Material fund changes
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Strategies [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Risks Change [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Summary of Change Legend [Text Block]
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
Updated Prospectus Phone Number (800) 441-7762
Updated Prospectus Web Address blackrock.com/fundreports
C000006074 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock Large Cap Focus Value Fund, Inc.
Class Name Investor A Shares
Trading Symbol MDBAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock Large Cap Focus Value Fund, Inc. (the “Fund”) for the period of July 1, 2025 to June 30, 2026.
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.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
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 $90 0.80%
Expenses Paid, Amount $ 90
Expense Ratio, Percent 0.80%
Factors Affecting Performance [Text Block]
How did the Fund perform last year?
  • For the reporting period ended June 30, 2026, the Fund's Investor A Shares returned 25.01%.
  • For the same period, the Fund’s benchmark, the Russell 1000 Index returned 22.01% and the Russell 1000 Value Index returned 27.09%.
What contributed to performance?
The largest positive contributor to the Fund’s performance was the allocation to the information technology sector, highlighted by holdings within the technology hardware, storage & peripherals industry. Positioning in both the consumer discretionary and materials sectors also contributed notably, particularly in the automobiles and containers & packaging subsectors, respectively.
What detracted from performance?
The largest detractor from performance was the allocation to the financials sector, where exposure to the financial services industry weighed most heavily on results. While there were no other detractors at the sector level during the period, exposure to the professional services and software industries also detracted from total return.
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: July 1, 2016 through June 30, 2026
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 25.01 % 11.58 % 11.27 %
Investor A Shares (with sales charge) 18.45 10.39 10.67
Russell 1000 Index 22.01 12.66 15.29
Russell 1000 Value Index 27.09 11.17 11.52
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.
Material Change Date Oct. 28, 2025
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 1,997,153,597
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 7,973,483
Investment Company Portfolio Turnover 91.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $1,997,153,597
Number of Portfolio Holdings 52
Net Investment Advisory Fees $7,973,483
Portfolio Turnover Rate 91%
Holdings [Text Block]
What did the Fund invest in?
(as of June 30, 2026)
Sector allocation
Sector(a) Percent of
Net Assets
Information Technology 17.6 %
Financials 17.6 %
Health Care 15.1 %
Industrials 12.9 %
Consumer Discretionary 12.0 %
Consumer Staples 5.6 %
Energy 4.7 %
Utilities 4.0 %
Communication Services 3.9 %
Materials 3.6 %
Real Estate 2.8 %
Short-Term Securities 0.6 %
Liabilities in Excess of Other Assets (0.4 )%
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(a)
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(b)Excludes short-term securities.
Material Fund Change [Text Block]
Material fund changes
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Strategies [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Risks Change [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Summary of Change Legend [Text Block]
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
Updated Prospectus Phone Number (800) 441-7762
Updated Prospectus Web Address blackrock.com/fundreports
C000006077 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock Large Cap Focus Value Fund, Inc.
Class Name Institutional Shares
Trading Symbol MABAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock Large Cap Focus Value Fund, Inc. (the “Fund”) for the period of July 1, 2025 to June 30, 2026.
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.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
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 $62 0.55%
Expenses Paid, Amount $ 62
Expense Ratio, Percent 0.55%
Factors Affecting Performance [Text Block]
How did the Fund perform last year?
  • For the reporting period ended June 30, 2026, the Fund's Institutional Shares returned 25.30%.
  • For the same period, the Fund’s benchmark, the Russell 1000 Index returned 22.01% and the Russell 1000 Value Index returned 27.09%.
What contributed to performance?
The largest positive contributor to the Fund’s performance was the allocation to the information technology sector, highlighted by holdings within the technology hardware, storage & peripherals industry. Positioning in both the consumer discretionary and materials sectors also contributed notably, particularly in the automobiles and containers & packaging subsectors, respectively.
What detracted from performance?
The largest detractor from performance was the allocation to the financials sector, where exposure to the financial services industry weighed most heavily on results. While there were no other detractors at the sector level during the period, exposure to the professional services and software industries also detracted from total return.
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: July 1, 2016 through June 30, 2026
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 25.30 % 11.87 % 11.57 %
Russell 1000 Index 22.01 12.66 15.29
Russell 1000 Value Index 27.09 11.17 11.52
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.
Material Change Date Oct. 28, 2025
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 1,997,153,597
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 7,973,483
Investment Company Portfolio Turnover 91.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $1,997,153,597
Number of Portfolio Holdings 52
Net Investment Advisory Fees $7,973,483
Portfolio Turnover Rate 91%
Holdings [Text Block]
What did the Fund invest in?
(as of June 30, 2026)
Sector allocation
Sector(a) Percent of
Net Assets
Information Technology 17.6 %
Financials 17.6 %
Health Care 15.1 %
Industrials 12.9 %
Consumer Discretionary 12.0 %
Consumer Staples 5.6 %
Energy 4.7 %
Utilities 4.0 %
Communication Services 3.9 %
Materials 3.6 %
Real Estate 2.8 %
Short-Term Securities 0.6 %
Liabilities in Excess of Other Assets (0.4 )%
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(a)
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(b)Excludes short-term securities.
Material Fund Change [Text Block]
Material fund changes
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Strategies [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Risks Change [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Summary of Change Legend [Text Block]
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
Updated Prospectus Phone Number (800) 441-7762
Updated Prospectus Web Address blackrock.com/fundreports
C000007847 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock Large Cap Focus Value Fund, Inc.
Class Name Class R Shares
Trading Symbol MRBVX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock Large Cap Focus Value Fund, Inc. (the “Fund”) for the period of July 1, 2025 to June 30, 2026.
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.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
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 $131 1.17%
Expenses Paid, Amount $ 131
Expense Ratio, Percent 1.17%
Factors Affecting Performance [Text Block]
How did the Fund perform last year?
  • For the reporting period ended June 30, 2026, the Fund's Class R Shares returned 24.54%.
  • For the same period, the Fund’s benchmark, the Russell 1000 Index returned 22.01% and the Russell 1000 Value Index returned 27.09%.
What contributed to performance?
The largest positive contributor to the Fund’s performance was the allocation to the information technology sector, highlighted by holdings within the technology hardware, storage & peripherals industry. Positioning in both the consumer discretionary and materials sectors also contributed notably, particularly in the automobiles and containers & packaging subsectors, respectively.
What detracted from performance?
The largest detractor from performance was the allocation to the financials sector, where exposure to the financial services industry weighed most heavily on results. While there were no other detractors at the sector level during the period, exposure to the professional services and software industries also detracted from total return.
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: July 1, 2016 through June 30, 2026
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 24.54 % 11.17 % 10.88 %
Russell 1000 Index 22.01 12.66 15.29
Russell 1000 Value Index 27.09 11.17 11.52
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.
Material Change Date Oct. 28, 2025
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 1,997,153,597
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 7,973,483
Investment Company Portfolio Turnover 91.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $1,997,153,597
Number of Portfolio Holdings 52
Net Investment Advisory Fees $7,973,483
Portfolio Turnover Rate 91%
Holdings [Text Block]
What did the Fund invest in?
(as of June 30, 2026)
Sector allocation
Sector(a) Percent of
Net Assets
Information Technology 17.6 %
Financials 17.6 %
Health Care 15.1 %
Industrials 12.9 %
Consumer Discretionary 12.0 %
Consumer Staples 5.6 %
Energy 4.7 %
Utilities 4.0 %
Communication Services 3.9 %
Materials 3.6 %
Real Estate 2.8 %
Short-Term Securities 0.6 %
Liabilities in Excess of Other Assets (0.4 )%
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(a)
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(b)Excludes short-term securities.
Material Fund Change [Text Block]
Material fund changes
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Strategies [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Risks Change [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Summary of Change Legend [Text Block]
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
Updated Prospectus Phone Number (800) 441-7762
Updated Prospectus Web Address blackrock.com/fundreports
C000152172 [Member]  
Shareholder Report [Line Items]  
Fund Name BlackRock Large Cap Focus Value Fund, Inc.
Class Name Class K Shares
Trading Symbol MBVKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about BlackRock Large Cap Focus Value Fund, Inc. (the “Fund”) for the period of July 1, 2025 to June 30, 2026.
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.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
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 $53 0.47%
Expenses Paid, Amount $ 53
Expense Ratio, Percent 0.47%
Factors Affecting Performance [Text Block]
How did the Fund perform last year?
  • For the reporting period ended June 30, 2026, the Fund's Class K Shares returned 25.46%.
  • For the same period, the Fund’s benchmark, the Russell 1000 Index returned 22.01% and the Russell 1000 Value Index returned 27.09%.
What contributed to performance?
The largest positive contributor to the Fund’s performance was the allocation to the information technology sector, highlighted by holdings within the technology hardware, storage & peripherals industry. Positioning in both the consumer discretionary and materials sectors also contributed notably, particularly in the automobiles and containers & packaging subsectors, respectively.
What detracted from performance?
The largest detractor from performance was the allocation to the financials sector, where exposure to the financial services industry weighed most heavily on results. While there were no other detractors at the sector level during the period, exposure to the professional services and software industries also detracted from total return.
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: July 1, 2016 through June 30, 2026
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 25.46 % 11.97 % 11.68 %
Russell 1000 Index 22.01 12.66 15.29
Russell 1000 Value Index 27.09 11.17 11.52
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.
Material Change Date Oct. 28, 2025
Updated Performance Information Location [Text Block] Visit blackrock.com for more recent performance information.
Net Assets $ 1,997,153,597
Holdings Count | Holding 52
Advisory Fees Paid, Amount $ 7,973,483
Investment Company Portfolio Turnover 91.00%
Additional Fund Statistics [Text Block]
Key Fund statistics
Net Assets $1,997,153,597
Number of Portfolio Holdings 52
Net Investment Advisory Fees $7,973,483
Portfolio Turnover Rate 91%
Holdings [Text Block]
What did the Fund invest in?
(as of June 30, 2026)
Sector allocation
Sector(a) Percent of
Net Assets
Information Technology 17.6 %
Financials 17.6 %
Health Care 15.1 %
Industrials 12.9 %
Consumer Discretionary 12.0 %
Consumer Staples 5.6 %
Energy 4.7 %
Utilities 4.0 %
Communication Services 3.9 %
Materials 3.6 %
Real Estate 2.8 %
Short-Term Securities 0.6 %
Liabilities in Excess of Other Assets (0.4 )%
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(a)
For purposes of this report, sector sub-classifications may differ from those utilized by the Fund for compliance purposes.
(b)
Excludes short-term securities.
Largest Holdings [Text Block]
Ten largest holdings
Security(b) Percent of
Net Assets
Amazon.com, Inc. 8.4 %
Microsoft Corp. 6.4 %
Wells Fargo & Co. 3.2 %
Citigroup, Inc. 3.0 %
First Citizens BancShares, Inc., Class A 2.8 %
British American Tobacco PLC, ADR 2.7 %
Merck & Co., Inc. 2.7 %
BP PLC, ADR 2.7 %
Hewlett Packard Enterprise Co. 2.6 %
Western Digital Corp. 2.5 %
(b)Excludes short-term securities.
Material Fund Change [Text Block]
Material fund changes
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Strategies [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Material Fund Change Risks Change [Text Block]
The Fund's Board previously approved certain changes to the Fund’s investment strategy and investment process. Under normal circumstances, the Fund seeks to invest at least 80% of its net assets (plus the amount of any borrowings for investment purposes) in large cap value equity securities and derivatives that provide investment exposure to such securities or to one or more market risk factors associated with such securities. These changes were effective on October 28, 2025.
Summary of Change Legend [Text Block]
This is a summary of certain changes to the Fund since June 30, 2025. For more complete information, you may review the Fund’s next prospectus, which we expect to be available approximately 120 days after June 30, 2026 at blackrock.com/fundreports or upon request by contacting us at (800) 441-7762.
Updated Prospectus Phone Number (800) 441-7762
Updated Prospectus Web Address blackrock.com/fundreports