v3.26.1
Shareholder Report
12 Months Ended
Mar. 31, 2026
USD ($)
Holding
Shareholder Report [Line Items]  
Document Type N-CSR/A
Amendment Flag false
Registrant Name TIAA-CREF Funds
Entity Central Index Key 0001084380
Entity Investment Company Type N-1A
Document Period End Date Mar. 31, 2026
C000202747 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Class W Shares
Trading Symbol TBBWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [1]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.77% for Class W Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      Since Inception
(9/28/18)
 
       
Class W Shares at NAV
     4.77%        0.98%        2.76%  
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      2.07
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go tohttps://www.nuveen.com/en‑us/mutual‑funds/prospectusesor call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $  10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
     $      28,812,835  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033991 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Retirement Class Shares
Trading Symbol TIDRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $54    0.53%
* Annualized for period less than one year.
Expenses Paid, Amount $ 54
Expense Ratio, Percent 0.53% [2]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.33% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Retirement Class Shares at NAV
   4.33%    0.45%    1.99%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
    
 
$    28,812,835
 
 
 
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000014635 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Class R6 Shares
Trading Symbol TIBDX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $29    0.28%
* Annualized for period less than one year.
Expenses Paid, Amount $ 29
Expense Ratio, Percent 0.28% [3]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.48% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   4.48%    0.69%    2.24%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
     $   28,812,835  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079556 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Premier Class Shares
Trading Symbol TIDPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at
https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
    Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment* 
     
Premier Class Shares
  $44    0.43% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 44
Expense Ratio, Percent 0.43% [4]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.44% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   4.44%    0.56%    2.08%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
     $    28,812,835  
Holdings [Text Block]
LOGO
LOGO
 
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162549 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Class I Shares
Trading Symbol TIBHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Class I Shares
  $44    0.43% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 44
Expense Ratio, Percent 0.43% [5]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.33% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
•  An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
•  Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
•  Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
•  Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Class I Shares at NAV
     4.33      0.55      2.13
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
     $    28,812,835  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033992 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Bond Fund
Class Name Class A Shares
Trading Symbol TIORX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Core Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $61    0.60%
* Annualized for period less than one year.
Expenses Paid, Amount $ 61
Expense Ratio, Percent 0.60% [6]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Bond Fund returned 4.26% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including small out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
Out‑of‑benchmark exposure to non‑agency mortgage-backed securities and an overweight to emerging-markets debt.
 
Security selection, especially within investment-grade corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   4.26%    0.40%    1.94%
       
Class A at maximum sales charge (Offering Price)
   0.35%    (0.36)%    1.55%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 10,171,187,634
Holdings Count | Holding 1,914
Advisory Fees Paid, Amount $ 28,812,835
Investment Company Portfolio Turnover 113.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $10,171,187,634  
Total number of portfolio holdings
     1,914  
Portfolio turnover (%)
     113%  
Total management fees paid for the year
     $    28,812,835  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033995 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Money Market Fund
Class Name Class A Shares
Trading Symbol TIRXX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Money Market Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $46    0.45%
* Annualized for period less than one year.
Expenses Paid, Amount $ 46
Expense Ratio, Percent 0.45% [7]
Net Assets $ 2,026,725,366
Holdings Count | Holding 73
Advisory Fees Paid, Amount $ 2,106,457
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,026,725,366  
Total number of portfolio holdings
     73  
Total management fees paid for the year
     $    2,106,457  
Holdings [Text Block]
LOGO
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162551 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Money Market Fund
Class Name Class I Shares
Trading Symbol TMHXX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Money Market Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website  https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $15    0.15%
* Annualized for period less than one year.
Expenses Paid, Amount $ 15
Expense Ratio, Percent 0.15% [8]
Net Assets $ 2,026,725,366
Holdings Count | Holding 73
Advisory Fees Paid, Amount $ 2,106,457
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,026,725,366  
Total number of portfolio holdings
     73  
Total management fees paid for the year
     $    2,106,457  
Holdings [Text Block]
LOGO
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079558 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Money Market Fund
Class Name Premier Class Shares
Trading Symbol TPPXX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Money Market Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment*
Premier Class Shares
  $28    0.27%
* Annualized for period less than one year.
Expenses Paid, Amount $ 28
Expense Ratio, Percent 0.27% [9]
Net Assets $ 2,026,725,366
Holdings Count | Holding 73
Advisory Fees Paid, Amount $ 2,106,457
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,026,725,366  
Total number of portfolio holdings
     73  
Total management fees paid for the year
     $    2,106,457  
Holdings [Text Block]
LOGO
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000014638 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Money Market Fund
Class Name Class R6 Shares
Trading Symbol TCIXX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Money Market Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $12    0.12%
* Annualized for period less than one year.
Expenses Paid, Amount $ 12
Expense Ratio, Percent 0.12% [10]
Net Assets $ 2,026,725,366
Holdings Count | Holding 73
Advisory Fees Paid, Amount $ 2,106,457
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,026,725,366  
Total number of portfolio holdings
     73  
Total management fees paid for the year
     $    2,106,457  
Holdings [Text Block]
LOGO
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033994 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Money Market Fund
Class Name Retirement Class Shares
Trading Symbol TIEXX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Money Market Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block]  You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $38    0.37%
* Annualized for period less than one year.
Expenses Paid, Amount $ 38
Expense Ratio, Percent 0.37% [11]
Net Assets $ 2,026,725,366
Holdings Count | Holding 73
Advisory Fees Paid, Amount $ 2,106,457
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,026,725,366  
Total number of portfolio holdings
     73  
Total management fees paid for the year
     $    2,106,457  
Holdings [Text Block]
LOGO
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000202755 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Class W Shares
Trading Symbol TCTWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [12]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.78% for Class W Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
An overweight to corporate bonds.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(9/28/18)
       
Class W Shares at NAV
   4.78%    3.11%    3.28%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.07%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
     $    4,521,242  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033275 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Retirement Class Shares
Trading Symbol TISRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $52    0.51%
* Annualized for period less than one year.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.51% [13]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.25% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
An overweight to corporate bonds.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Retirement Class Shares at NAV
   4.25%    2.57%    2.37%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
     $   4,521,242  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033276 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Class R6 Shares
Trading Symbol TISIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $27    0.26%
* Annualized for period less than one year.
Expenses Paid, Amount $ 27
Expense Ratio, Percent 0.26% [14]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.51% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
An overweight to corporate bonds.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   4.51%    2.82%    2.62%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
     $    4,521,242  
Holdings [Text Block]
 
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079571 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Premier Class Shares
Trading Symbol TSTPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
    Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment* 
     
Premier Class Shares
  $42    0.41% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 42
Expense Ratio, Percent 0.41% [15]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.35% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
An overweight to corporate bonds.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   4.35%    2.67%    2.47%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
     $    4,521,242  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block]  Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162566 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Class I Shares
Trading Symbol TCTHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Class I Shares
  $30    0.29% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 30
Expense Ratio, Percent 0.29% [16]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.37% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
•  Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
•  An overweight to corporate bonds.
 
Top detractors from relative performance
 
•  Yield curve positioning in U.S. Treasuries.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   4.37%    2.75%    2.56%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
   $ 4,521,242  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en-us/mutual-funds/prospectuses or upon request at (800) 257-8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en-us/mutual-funds/prospectuses or upon request at (800) 257-8787.
Updated Prospectus Phone Number (800) 257-8787
Updated Prospectus Web Address https://www.nuveen.com/en-us/mutual-funds/prospectuses
C000033274 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Fund
Class Name Class A Shares
Trading Symbol TCTRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Short Term Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $60    0.59%
* Annualized for period less than one year.
Expenses Paid, Amount $ 60
Expense Ratio, Percent 0.59% [17]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Fund returned 4.17% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
Out‑of‑benchmark exposure to mortgage-backed securities, commercial mortgage-backed securities and asset-backed securities.
 
An overweight to corporate bonds.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   4.17%    2.52%    2.32%
       
Class A at maximum sales charge (Offering Price)
   1.56%    2.01%    2.06%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 1,734,899,596
Holdings Count | Holding 293
Advisory Fees Paid, Amount $ 4,521,242
Investment Company Portfolio Turnover 189.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $1,734,899,596  
Total number of portfolio holdings
     293  
Portfolio turnover (%)
     189%  
Total management fees paid for the year
     $    4,521,242  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033277 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Class A Shares
Trading Symbol TIYRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $70    0.68%
* Annualized for period less than one year.
Expenses Paid, Amount $ 70
Expense Ratio, Percent 0.68% [18]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen High Yield Fund returned 7.17% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
Top contributors to relative performance
 
Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
 
Security selection within the software/services industry.
 
Security selection within the health facilities industry.
 
Top detractors from relative performance
 
Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
 
Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
 
Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
 
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   7.17%    4.11%    5.32%
       
Class A at maximum sales charge (Offering Price)
   2.04%    3.09%    4.81%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
   7.04%    3.95%    5.67%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
     $    7,149,632  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162567 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Class I Shares
Trading Symbol TIHHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Class I Shares
  $52    0.50% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.50% [19]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen High Yield Fund returned 7.36% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
Top contributors to relative performance
 
•  Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
 
•  Security selection within the software/services industry.
 
•  Security selection within the health facilities industry.
 
Top detractors from relative performance
 
•  Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
 
•  Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
 
•  Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   7.36%    4.27%    5.49%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
   7.04%    3.95%    5.67%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
     $    7,149,632  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079572 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Premier Class Shares
Trading Symbol TIHPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
    Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment* 
     
Premier Class Shares
  $53    0.51% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 53
Expense Ratio, Percent 0.51% [20]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen High Yield Fund returned 7.35% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
Top contributors to relative performance
 
Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
 
Security selection within the software/services industry.
 
Security selection within the health facilities industry.
 
Top detractors from relative performance
 
Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
 
Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
 
Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   7.35%    4.27%    5.47%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
   7.04%    3.95%    5.67%
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
     $    7,149,632  
Holdings [Text Block]
LOGO
   LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033279 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Class R6 Shares
Trading Symbol TIHYX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $37    0.36%
* Annualized for period less than one year.
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.36% [21]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
   
The Nuveen High Yield Fund returned 7.51% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
 
   
Top contributors to relative performance
 
 
   
Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
 
   
Security selection within the software/services industry.
 
   
Security selection within the health facilities industry.
 
   
Top detractors from relative performance
 
 
   
Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
 
   
Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
 
   
Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Class R6 Shares at NAV
     7.51      4.40      5.62
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
     7.04      3.95      5.67
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
   $     7,149,632  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033278 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Retirement Class Shares
Trading Symbol TIHRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $63    0.61%
* Annualized for period less than one year.
Expenses Paid, Amount $ 63
Expense Ratio, Percent 0.61% [22]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
   
The Nuveen High Yield Fund returned 7.25% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
   
Top contributors to relative performance
 
   
Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
   
Security selection within the software/services industry.
   
Security selection within the health facilities industry.
   
Top detractors from relative performance
 
   
Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
   
Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
   
Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Retirement Class Shares at NAV
     7.25      4.15      5.35
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
     7.04      3.95      5.67
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
   $     7,149,632  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000202756 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen High Yield Fund
Class Name Class W Shares
Trading Symbol TIHWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen High Yield Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block] This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [23]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen High Yield Fund returned 7.90% for Class W Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index, which returned 7.04%.
 
Top contributors to relative performance
 
Security selection within the specialty retail industry, driven by an overweight to The Michaels Companies.
 
Security selection within the software/services industry.
 
Security selection within the health facilities industry.
 
Top detractors from relative performance
 
Security selection and an overweight position in the rail industry, including an overweight to Brightline East.
 
Security selection within the telecom – wireline integrated & services industry, including an overweight to LCPR Financing.
 
Security selection within the building materials industry, including an overweight to Cornerstone Building Brands, Inc.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(9/28/18)
       
Class W Shares at NAV
   7.90%    4.77%    4.99%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.07%
       
ICE BofA BB‑B U.S. Cash Pay High Yield Constrained Index
   7.04%    3.95%    4.90%
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,186,139,486
Holdings Count | Holding 370
Advisory Fees Paid, Amount $ 7,149,632
Investment Company Portfolio Turnover 48.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $ 2,186,139,486  
Total number of portfolio holdings
     370  
Portfolio turnover (%)
     48%  
Total management fees paid for the year
     $     7,149,632  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Updates: Effective April 1, 2025, Jean Lin retired and is no longer a portfolio manager of the Fund. Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000202758 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Class W Shares
Trading Symbol TCBWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [24]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Plus Bond Fund returned 4.79% for Class W Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
 
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(9/28/18)
       
Class W Shares at NAV
   4.79%    1.25%    3.00%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.07%
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $  4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
     $     13,064,399  
Holdings [Text Block]
LOGO
LOGO
 
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033284 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Retirement Class Shares
Trading Symbol TCBRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $55    0.54%
* Annualized for period less than one year.
Expenses Paid, Amount $ 55
Expense Ratio, Percent 0.54% [25]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
   
The Nuveen Core Plus Bond Fund returned 4.23% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
   
Top contributors to relative performance
 
   
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
   
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
   
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
   
Top detractors from relative performance
 
   
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Retirement Class Shares at NAV
     4.23      0.68      2.27
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
   $    13,064,399  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033285 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Class R6 Shares
Trading Symbol TIBFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $30    0.29%
* Annualized for period less than one year.
Expenses Paid, Amount $ 30
Expense Ratio, Percent 0.29% [26]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
   
The Nuveen Core Plus Bond Fund returned 4.49% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
   
Top contributors to relative performance
 
   
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
   
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
   
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
   
Top detractors from relative performance
 
   
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Class R6 Shares at NAV
     4.49      0.95      2.53
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go tohttps://www.nuveen.com/en‑us/mutual‑funds/prospectusesor call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
   $    13,064,399  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079574 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Premier Class Shares
Trading Symbol TBPPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
    Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment* 
     
Premier Class Shares
  $46    0.45% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 46
Expense Ratio, Percent 0.45% [27]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Plus Bond Fund returned 4.33% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
 
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   4.33%    0.77%    2.37%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go tohttps://www.nuveen.com/en‑us/mutual‑funds/prospectusesor call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
     $   13,064,399  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162569 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Class I Shares
Trading Symbol TCBHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $37    0.36%
* Annualized for period less than one year.
Expenses Paid, Amount $ 37
Expense Ratio, Percent 0.36% [28]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Plus Bond Fund returned 4.41% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
 
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
 
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   4.41%    0.85%    2.45%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
     $   13,064,399  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033283 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Plus Bond Fund
Class Name Class A Shares
Trading Symbol TCBPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Core Plus Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $64    0.63%
* Annualized for period less than one year.
Expenses Paid, Amount $ 64
Expense Ratio, Percent 0.63% [29]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
   
The Nuveen Core Plus Bond Fund returned 4.14% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
   
Top contributors to relative performance
 
   
An overweight to corporate bonds, including out‑of‑benchmark allocations to high-yield and emerging-markets corporate bonds and a corresponding underweight to U.S. Treasuries.
   
An overweight to emerging-markets debt and out‑of‑benchmark exposure to non‑agency mortgage-backed securities.
   
Security selection, especially within corporate bonds and commercial mortgage-backed securities.
   
Top detractors from relative performance
 
   
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Class A Shares at NAV (excluding maximum sales charge)
     4.14      0.62      2.20
       
Class A at maximum sales charge (Offering Price)
     0.24      (0.14 )%       1.81
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 4,420,052,522
Holdings Count | Holding 1,605
Advisory Fees Paid, Amount $ 13,064,399
Investment Company Portfolio Turnover 121.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 4,420,052,522  
Total number of portfolio holdings
     1,605  
Portfolio turnover (%)
     121%  
Total management fees paid for the year
   $    13,064,399  
Holdings [Text Block]
LOGO
LOGO
(1) Affiliated investment.
(2) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio Manager Update: Effective July 1, 2025, Kevin Lorenz retired and is no longer a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033286 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund
Class Name Class A Shares
Trading Symbol TIXRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $60    0.59%
* Annualized for period less than one year.
Expenses Paid, Amount $ 60
Expense Ratio, Percent 0.59% [30]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
   
The Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund returned 4.15% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg 10‑Year Municipal Bond Index, which returned 4.81%.
 
   
Top contributors to relative performance
 
   
Security selection in the lease backed and local GO sectors.
   
An overweight to the housing sector.
   
Exposure to the utility and education sectors.
   
Top detractors from relative performance
 
   
Exposure to the state GO, special tax and water/sewer sectors.
   
Yield curve positioning.
   
Security selection in the industrial development, health care and transportation sectors.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year      10‑Year  
       
Class A Shares at NAV (excluding maximum sales charge)
     4.15      0.31      1.60
       
Class A at maximum sales charge (Offering Price)
     1.00      (0.31 )%       1.30
       
Bloomberg Municipal Bond Index
     4.29      0.84      2.16
       
Bloomberg 10‑Year Municipal Bond Index
     4.81      1.00      2.26
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 192,196,208
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 491,983
Investment Company Portfolio Turnover 14.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 192,196,208  
Total number of portfolio holdings
     187  
Portfolio turnover (%)
     14%  
Total management fees paid for the year
   $     491,983  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162570 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund
Class Name Class I Shares
Trading Symbol TIXHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $35    0.34%
* Annualized for period less than one year.
Expenses Paid, Amount $ 35
Expense Ratio, Percent 0.34% [31]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund returned 4.41% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg 10‑Year Municipal Bond Index, which returned 4.81%.
 
Top contributors to relative performance
 
Security selection in the lease backed and local GO sectors.
 
An overweight to the housing sector.
 
Exposure to the utility and education sectors.
 
Top detractors from relative performance
 
Exposure to the state GO, special tax and water/sewer sectors.
 
Yield curve positioning.
 
Security selection in the industrial development, health care and transportation sectors.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
                                                                                
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   4.41%    0.50%    1.81%
       
Bloomberg Municipal Bond Index
   4.29%    0.84%    2.16%
       
Bloomberg 10‑Year Municipal Bond Index
   4.81%    1.00%    2.26%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 192,196,208
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 491,983
Investment Company Portfolio Turnover 14.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $192,196,208  
Total number of portfolio holdings
     187  
Portfolio turnover (%)
     14%  
Total management fees paid for the year
     $    491,983  
Holdings [Text Block]
LOGO
  LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000033287 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund
Class Name Class R6 Shares
Trading Symbol TITIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $31    0.30%
* Annualized for period less than one year.
Expenses Paid, Amount $ 31
Expense Ratio, Percent 0.30% [32]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen 5‑15 Year Laddered Tax Exempt Bond Fund returned 4.45% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg 10‑Year Municipal Bond Index, which returned 4.81%.
 
Top contributors to relative performance
 
Security selection in the lease backed and local GO sectors.
 
An overweight to the housing sector.
 
Exposure to the utility and education sectors.
 
Top detractors from relative performance
 
Exposure to the state GO, special tax and water/sewer sectors.
 
Yield curve positioning.
 
Security selection in the industrial development, health care and transportation sectors.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   4.45%    0.58%    1.88%
       
Bloomberg Municipal Bond Index
   4.29%    0.84%    2.16%
       
Bloomberg 10‑Year Municipal Bond Index
   4.81%    1.00%    2.26%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 192,196,208
Holdings Count | Holding 187
Advisory Fees Paid, Amount $ 491,983
Investment Company Portfolio Turnover 14.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $192,196,208  
Total number of portfolio holdings
     187  
Portfolio turnover (%)
     14%  
Total management fees paid for the year
     $    491,983  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000202762 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Class W Shares
Trading Symbol TBIWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [33]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Class W Shares at net asset value (NAV) was 4.39% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
Despite the effect of certain expenses incurred by the Fund that are not incurred by the benchmark index, the Fund’s return at NAV outperformed that of the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(9/28/18)
       
Class W Shares at NAV
   4.39%    0.31%    2.07%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.07%
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $  21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $      14,535,016  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079523 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Class R6 Shares
Trading Symbol TBIIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en-us/mutual-funds/prospectuses. You can also request this information by contacting us at (800) 257-8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257-8787
Additional Information Website https://www.nuveen.com/en-us/mutual-funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $7    0.07%
* Annualized for period less than one year.
Expenses Paid, Amount $ 7
Expense Ratio, Percent 0.07% [34]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Class R6 Shares at net asset value (NAV) was 4.32% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   4.32%    0.25%    1.58%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $    14,535,016  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079524 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Retirement Class Shares
Trading Symbol TBIRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $33    0.32%
* Annualized for period less than one year.
Expenses Paid, Amount $ 33
Expense Ratio, Percent 0.32% [35]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Retirement Class Shares at net asset value (NAV) was 4.06% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Retirement Class Shares at NAV
   4.06%    0.01%    1.34%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $    14,535,016  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079525 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Premier Class Shares
Trading Symbol TBIPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Premier Class Shares
  $22    0.22%
* Annualized for period less than one year.
Expenses Paid, Amount $ 22
Expense Ratio, Percent 0.22% [36]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Premier Class Shares at net asset value (NAV) was 4.17% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   4.17%    0.10%    1.43%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $    14,535,016  
Holdings [Text Block]
LOGO
LOGO
 
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162579 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Class I Shares
Trading Symbol TBIAX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $17    0.17%
* Annualized for period less than one year.
Expenses Paid, Amount $ 17
Expense Ratio, Percent 0.17% [37]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Class I Shares at net asset value (NAV) was 4.22% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
                                                              
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   4.22%    0.15%    1.48%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $    14,535,016  
Holdings [Text Block]
LOGO
  LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000079526 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Bond Index Fund
Class Name Class A Shares
Trading Symbol TBILX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $41    0.40%
* Annualized for period less than one year.
Expenses Paid, Amount $ 41
Expense Ratio, Percent 0.40% [38]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Bond Index Fund’s total return for Class A Shares at net asset value (NAV) was 3.98% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. Aggregate Bond Index, returned 4.35%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   3.98%    (0.07)%    1.26%
       
Class A at maximum sales charge (Offering Price)
   0.05%    (0.82)%    0.88%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 21,161,202,913
Holdings Count | Holding 8,530
Advisory Fees Paid, Amount $ 14,535,016
Investment Company Portfolio Turnover 28.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $21,161,202,913  
Total number of portfolio holdings
     8,530  
Portfolio turnover (%)
     28%  
Total management fees paid for the year
     $    14,535,016  
Holdings [Text Block]
LOGO
LOGO
 
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000117723 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Impact Bond Fund
Class Name Class A Shares
Trading Symbol TSBRX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Core Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $69    0.67%
* Annualized for period less than one year.
Expenses Paid, Amount $ 69
Expense Ratio, Percent 0.67% [39]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Impact Bond Fund returned 4.63% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including a small out‑of‑benchmark allocation to high-yield corporate bonds, out‑of‑benchmark exposure to non‑agency mortgage-backed securities, and a corresponding underweight to U.S. Treasuries.
 
Security selection within investment-grade corporate bonds and commercial mortgage-backed securities (CMBS).
 
An out‑of‑benchmark allocation to municipal bonds, as well as overweights to government credit securities, CMBS, and asset‑backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   4.63%    0.26%    1.79%
       
Class A at maximum sales charge (Offering Price)
   0.70%    (0.51)%    1.41%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 7,491,858,652
Holdings Count | Holding 1,103
Advisory Fees Paid, Amount $ 22,807,929
Investment Company Portfolio Turnover 143.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $7,491,858,652  
Total number of portfolio holdings
     1,103  
Portfolio turnover (%)
     143%  
Total management fees paid for the year
     $   22,807,929  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162598 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Impact Bond Fund
Class Name Class I Shares
Trading Symbol TSBHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Core Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Class I Shares
  $42    0.41% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 42
Expense Ratio, Percent 0.41% [40]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Impact Bond Fund returned 4.68% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including a small out‑of‑benchmark allocation to high-yield corporate bonds, out‑of‑benchmark exposure to non‑agency mortgage-backed securities, and a corresponding underweight to U.S. Treasuries.
 
Security selection within investment-grade corporate bonds and commercial mortgage-backed securities (CMBS).
 
An out‑of‑benchmark allocation to municipal bonds, as well as overweights to government credit securities, CMBS, and asset-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   4.68%    0.46%    1.99%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 7,491,858,652
Holdings Count | Holding 1,103
Advisory Fees Paid, Amount $ 22,807,929
Investment Company Portfolio Turnover 143.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 7,491,858,652  
Total number of portfolio holdings
     1,103  
Portfolio turnover (%)
     143%  
Total management fees paid for the year
   $ 22,807,929  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000117722 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Impact Bond Fund
Class Name Premier Class Shares
Trading Symbol TSBPX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Core Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Premier Class Shares
  $51    0.50%
* Annualized for period less than one year.
Expenses Paid, Amount $ 51
Expense Ratio, Percent 0.50% [41]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Impact Bond Fund returned 4.70% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including a small out‑of‑benchmark allocation to high-yield corporate bonds, out‑of‑benchmark exposure to non‑agency mortgage-backed securities, and a corresponding underweight to U.S. Treasuries.
 
Security selection within investment-grade corporate bonds and commercial mortgage-backed securities (CMBS).
 
An out‑of‑benchmark allocation to municipal bonds, as well as overweights to government credit securities, CMBS, and asset-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   4.70%    0.35%    1.91%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 7,491,858,652
Holdings Count | Holding 1,103
Advisory Fees Paid, Amount $ 22,807,929
Investment Company Portfolio Turnover 143.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 7,491,858,652  
Total number of portfolio holdings
     1,103  
Portfolio turnover (%)
     143%  
Total management fees paid for the year
   $ 22,807,929  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000117721 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Impact Bond Fund
Class Name Class R6 Shares
Trading Symbol TSBIX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Core Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
Class R6 Shares
  $36    0.35%
* Annualized for period less than one year.
Expenses Paid, Amount $ 36
Expense Ratio, Percent 0.35% [42]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Impact Bond Fund returned 4.86% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including a small out‑of‑benchmark allocation to high-yield corporate bonds, out‑of‑benchmark exposure to non‑agency mortgage-backed securities, and a corresponding underweight to U.S. Treasuries.
 
Security selection within investment-grade corporate bonds and commercial mortgage-backed securities (CMBS).
 
An out‑of‑benchmark allocation to municipal bonds, as well as overweights to government credit securities, CMBS, and asset-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   4.86%    0.52%    2.07%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 7,491,858,652
Holdings Count | Holding 1,103
Advisory Fees Paid, Amount $ 22,807,929
Investment Company Portfolio Turnover 143.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $7,491,858,652  
Total number of portfolio holdings
     1,103  
Portfolio turnover (%)
     143%  
Total management fees paid for the year
     $   22,807,929  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en-us/mutual-funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en-us/mutual-funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en-us/mutual-funds/prospectuses
C000117724 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Core Impact Bond Fund
Class Name Retirement Class Shares
Trading Symbol TSBBX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Core Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $61    0.60%
* Annualized for period less than one year.
Expenses Paid, Amount $ 61
Expense Ratio, Percent 0.60% [43]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Core Impact Bond Fund returned 4.60% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg U.S. Aggregate Bond Index, which returned 4.35%.
 
Top contributors to relative performance
 
An overweight to corporate bonds, including a small out‑of‑benchmark allocation to high-yield corporate bonds, out‑of‑benchmark exposure to non‑agency mortgage-backed securities, and a corresponding underweight to U.S. Treasuries.
 
Security selection within investment-grade corporate bonds and commercial mortgage-backed securities (CMBS).
 
An out‑of‑benchmark allocation to municipal bonds, as well as overweights to government credit securities, CMBS, and asset-backed securities.
 
Top detractors from relative performance
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Retirement Class Shares at NAV
   4.60%    0.27%    1.81%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 7,491,858,652
Holdings Count | Holding 1,103
Advisory Fees Paid, Amount $ 22,807,929
Investment Company Portfolio Turnover 143.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $7,491,858,652  
Total number of portfolio holdings
     1,103  
Portfolio turnover (%)
     143%  
Total management fees paid for the year
     $   22,807,929  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000202767 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Class W Shares
Trading Symbol TTBWX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class W Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class W Shares
  $0    0.00%
* Annualized for period less than one year.
Expenses Paid, Amount $ 0
Expense Ratio, Percent 0.00% [44]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Class W Shares at net asset value (NAV) was 3.96% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, returned 3.96%.
 
Despite the effect of certain expenses incurred by the Fund that are not incurred by the benchmark index, the Fund’s return at NAV matched that of the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(9/28/18)
       
Class W Shares at NAV
   3.96%    2.08%    2.51%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.07%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Sep. 28, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
     $    1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000158753 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Retirement Class Shares
Trading Symbol TESHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Retirement Class Shares
  $33    0.32% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 33
Expense Ratio, Percent 0.32% [45]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Retirement Class Shares at net asset value (NAV) was 3.64% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, returned 3.96%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year      5‑Year     
10‑Year
 
       
Retirement Class Shares at NAV
     3.64      1.75      1.67
       
Bloomberg U.S. Aggregate Bond Index
     4.35      0.31      1.70
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
     3.96      2.04      2.02
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
   $ 1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000158750 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Class R6 Shares
Trading Symbol TNSHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $7    0.07%
* Annualized for period less than one year.
Expenses Paid, Amount $ 7
Expense Ratio, Percent 0.07% [46]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Class R6 Shares at net asset value (NAV) was 3.89% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, returned 3.96%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class R6 Shares at NAV
   3.89%    2.00%    1.93%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
     $    1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000158751 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Premier Class Shares
Trading Symbol TPSHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
    Cost of a 
$10,000 investment 
  Costs paid as a percentage of 
$10,000 investment* 
     
Premier Class Shares
  $24    0.24% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 24
Expense Ratio, Percent 0.24% [47]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Premier Class Shares at net asset value (NAV) was 3.72% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1-3 Year Government/Credit Bond Index, returned 3.96%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Premier Class Shares at NAV
   3.72%    1.83%    1.75%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
     $    1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block]  Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000162603 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Class I Shares
Trading Symbol TTBHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website  https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of 
$10,000 investment* 
     
Class I Shares
  $19    0.19% 
* Annualized for period less than one year.
Expenses Paid, Amount $ 19
Expense Ratio, Percent 0.19% [48]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Class I Shares at net asset value (NAV) was 3.87% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, returned 3.96%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    10‑Year
       
Class I Shares at NAV
   3.87%    1.87%    1.81%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
   $ 1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000158752 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Term Bond Index Fund
Class Name Class A Shares
Trading Symbol TRSHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Short Term Bond Index Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website  https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $40    0.39%
* Annualized for period less than one year.
Expenses Paid, Amount $ 40
Expense Ratio, Percent 0.39% [49]
Factors Affecting Performance [Text Block]
 
How did the Fund perform last year? What affected the Fund’s performance?
 
Performance Highlights
 
The Nuveen Short Term Bond Index Fund’s total return for Class A Shares at net asset value (NAV) was 3.67% for the 12 months ended March 31, 2026. The Fund’s index, the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, returned 3.96%.
 
The difference between the Fund’s total return at NAV and that of the index is attributable to management fees and other expenses incurred by the Fund that are not incurred by the index.
 
The Fund had a risk profile similar to that of its benchmark. As such, there were no material contributors or detractors relative to the Fund’s benchmark during the period.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year   
10‑Year
       
Class A Shares at NAV (excluding maximum sales charge)
   3.67%    1.67%    1.59%
       
Class A at maximum sales charge (Offering Price)
   1.05%    1.15%    1.33%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    1.70%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.02%
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 2,448,172,264
Holdings Count | Holding 995
Advisory Fees Paid, Amount $ 1,236,379
Investment Company Portfolio Turnover 63.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $2,448,172,264  
Total number of portfolio holdings
     995  
Portfolio turnover (%)
     63%  
Total management fees paid for the year
     $    1,236,379  
Holdings [Text Block]
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
   
Portfolio manager updates: Effective January 23, 2026, Joseph Spinelli was added as a portfolio manager of the Fund and Vivian Liu was removed as a portfolio manager of the Fund.
 
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205813 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Green Bond Fund
Class Name Class A Shares
Trading Symbol TGROX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Green Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $78    0.76%
* Annualized for period less than one year.
Expenses Paid, Amount $ 78
Expense Ratio, Percent 0.76% [50]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Green Bond Fund returned 4.14% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg MSCI U.S. Green Bond Index, which returned 4.66%.
 
Top contributors to relative performance
 
An out‑of‑benchmark allocation to high-yield corporate bonds.
 
Security selection and an overweight to commercial mortgage-backed securities.
 
Out‑of‑benchmark exposure to municipal bonds and asset-backed securities.
 
Top detractors from relative performance
 
Exposure to government-agency and -credit securities, particularly emerging-markets debt.
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class A Shares at NAV (excluding maximum sales charge)
   4.14%    0.45%    2.35%
       
Class A at maximum sales charge (Offering Price)
   0.29%    (0.31)%    1.83%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg MSCI U.S. Green Bond Index
   4.66%    0.95%    2.80%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 184,532,910
Holdings Count | Holding 254
Advisory Fees Paid, Amount $ 721,762
Investment Company Portfolio Turnover 31.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $184,532,910  
Total number of portfolio holdings
     254  
Portfolio turnover (%)
     31%  
Total management fees paid for the year
     $    721,762  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205815 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Green Bond Fund
Class Name Class I Shares
Trading Symbol TGRKX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Green Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $52    0.51%
* Annualized for period less than one year.
Expenses Paid, Amount $ 52
Expense Ratio, Percent 0.51% [51]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Green Bond Fund returned 4.40% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg MSCI U.S. Green Bond Index, which returned 4.66%.
 
Top contributors to relative performance
 
An out‑of‑benchmark allocation to high-yield corporate bonds.
 
Security selection and an overweight to commercial mortgage-backed securities.
 
Out‑of‑benchmark exposure to municipal bonds and asset-backed securities.
 
Top detractors from relative performance
 
Exposure to government-agency and -credit securities, particularly emerging-markets debt.
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class I Shares at NAV
   4.40%    0.70%    2.60%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg MSCI U.S. Green Bond Index
   4.66%    0.95%    2.80%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 184,532,910
Holdings Count | Holding 254
Advisory Fees Paid, Amount $ 721,762
Investment Company Portfolio Turnover 31.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $184,532,910  
Total number of portfolio holdings
     254  
Portfolio turnover (%)
     31%  
Total management fees paid for the year
     $    721,762  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205812 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Green Bond Fund
Class Name Premier Class Shares
Trading Symbol TGRLX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Green Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
 
Costs paid as a percentage of
$10,000 investment*
     
Premier Class Shares
  $58    0.57%
* Annualized for period less than one year.
Expenses Paid, Amount $ 58
Expense Ratio, Percent 0.57% [52]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Green Bond Fund returned 4.33% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg MSCI U.S. Green Bond Index, which returned 4.66%.
 
Top contributors to relative performance
 
An out‑of‑benchmark allocation to high-yield corporate bonds.
 
Security selection and an overweight to commercial mortgage-backed securities.
 
Out‑of‑benchmark exposure to municipal bonds and asset-backed securities.
 
Top detractors from relative performance
 
Exposure to government-agency and -credit securities, particularly emerging-markets debt.
 
Yield curve positioning.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Premier Class Shares at NAV
   4.33%    0.63%    2.51%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg MSCI U.S. Green Bond Index
   4.66%    0.95%    2.80%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 184,532,910
Holdings Count | Holding 254
Advisory Fees Paid, Amount $ 721,762
Investment Company Portfolio Turnover 31.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $184,532,910  
Total number of portfolio holdings
     254  
Portfolio turnover (%)
     31%  
Total management fees paid for the year
     $    721,762  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205811 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Green Bond Fund
Class Name Class R6 Shares
Trading Symbol TGRNX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Green Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information athttps://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $43    0.42%
* Annualized for period less than one year.
Expenses Paid, Amount $ 43
Expense Ratio, Percent 0.42% [53]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Green Bond Fund returned 4.49% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund performed in line with the Bloomberg MSCI U.S. Green Bond Index, which returned 4.66%.
 
Top contributors to relative performance
 
An out‑of‑benchmark allocation to high-yield corporate bonds.
 
Security selection and an overweight to commercial mortgage-backed securities.
 
Out‑of‑benchmark exposure to municipal bonds and asset-backed securities.
 
Top detractors from relative performance
 
Exposure to government-agency and -credit securities, particularly emerging-markets debt.
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class R6 Shares at NAV
   4.49%    0.78%    2.66%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg MSCI U.S. Green Bond Index
   4.66%    0.95%    2.80%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 184,532,910
Holdings Count | Holding 254
Advisory Fees Paid, Amount $ 721,762
Investment Company Portfolio Turnover 31.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
   $ 184,532,910  
Total number of portfolio holdings
     254  
Portfolio turnover (%)
     31%  
Total management fees paid for the year
   $     721,762  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205814 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Green Bond Fund
Class Name Retirement Class Shares
Trading Symbol TGRMX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Green Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $68    0.67%
* Annualized for period less than one year.
Expenses Paid, Amount $ 68
Expense Ratio, Percent 0.67% [54]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Green Bond Fund returned 4.23% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund underperformed the Bloomberg MSCI U.S. Green Bond Index, which returned 4.66%.
 
Top contributors to relative performance
 
An out‑of‑benchmark allocation to high-yield corporate bonds.
 
Security selection and an overweight to commercial mortgage-backed securities.
 
Out‑of‑benchmark exposure to municipal bonds and asset-backed securities.
 
Top detractors from relative performance
 
Exposure to government-agency and -credit securities, particularly emerging-markets debt.
 
Yield curve positioning.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Retirement Class Shares at NAV
   4.23%    0.55%    2.47%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg MSCI U.S. Green Bond Index
   4.66%    0.95%    2.80%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 184,532,910
Holdings Count | Holding 254
Advisory Fees Paid, Amount $ 721,762
Investment Company Portfolio Turnover 31.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $184,532,910  
Total number of portfolio holdings
     254  
Portfolio turnover (%)
     31%  
Total management fees paid for the year
     $    721,762  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205819 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Duration Impact Bond Fund
Class Name Retirement Class Shares
Trading Symbol TSDDX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Retirement Class Shares of the Nuveen Short Duration Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Retirement Class Shares
  $60    0.59%
* Annualized for period less than one year.
Expenses Paid, Amount $ 60
Expense Ratio, Percent 0.59% [55]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Duration Impact Bond Fund returned 4.35% for Retirement Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
An overweight position and security selection in corporate bonds.
 
Out‑of‑benchmark exposure to asset-backed securities, commercial mortgage-backed securities and municipal bonds.
 
Overweights to government-credit and -agency securities.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Retirement Class Shares at NAV
   4.35%    2.31%    2.83%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 347,309,345
Holdings Count | Holding 268
Advisory Fees Paid, Amount $ 469,315
Investment Company Portfolio Turnover 305.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $347,309,345  
Total number of portfolio holdings
     268  
Portfolio turnover (%)
     305%  
Total management fees paid for the year
     $    469,315  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205816 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Duration Impact Bond Fund
Class Name Class R6 Shares
Trading Symbol TSDJX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class R6 Shares of the Nuveen Short Duration Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class R6 Shares
  $35    0.34%
* Annualized for period less than one year.
Expenses Paid, Amount $ 35
Expense Ratio, Percent 0.34% [56]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Duration Impact Bond Fund returned 4.60% for Class R6 Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
An overweight position and security selection in corporate bonds.
 
Out‑of‑benchmark exposure to asset-backed securities, commercial mortgage-backed securities and municipal bonds.
 
Overweights to government-credit and -agency securities.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class R6 Shares at NAV
   4.60%    2.56%    3.08%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 347,309,345
Holdings Count | Holding 268
Advisory Fees Paid, Amount $ 469,315
Investment Company Portfolio Turnover 305.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $347,309,345  
Total number of portfolio holdings
     268  
Portfolio turnover (%)
     305%  
Total management fees paid for the year
     $    469,315  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205817 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Duration Impact Bond Fund
Class Name Premier Class Shares
Trading Symbol TSDFX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Premier Class Shares of the Nuveen Short Duration Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website  https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Premier Class Shares
  $50    0.49%
* Annualized for period less than one year.
Expenses Paid, Amount $ 50
Expense Ratio, Percent 0.49% [57]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Duration Impact Bond Fund returned 4.54% for Premier Class Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
An overweight position and security selection in corporate bonds.
 
Out‑of‑benchmark exposure to asset-backed securities, commercial mortgage-backed securities and municipal bonds.
 
Overweights to government-credit and -agency securities.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
 
 
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Premier Class Shares at NAV
   4.54%    2.43%    2.94%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block]  The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 347,309,345
Holdings Count | Holding 268
Advisory Fees Paid, Amount $ 469,315
Investment Company Portfolio Turnover 305.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $347,309,345  
Total number of portfolio holdings
     268  
Portfolio turnover (%)
     305%  
Total management fees paid for the year
     $    469,315  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205820 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Duration Impact Bond Fund
Class Name Class I Shares
Trading Symbol TSDHX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class I Shares of the Nuveen Short Duration Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website  https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class I Shares
  $39    0.38%
* Annualized for period less than one year.
Expenses Paid, Amount $ 39
Expense Ratio, Percent 0.38% [58]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Duration Impact Bond Fund returned 4.45% for Class I Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
An overweight position and security selection in corporate bonds.
 
Out‑of‑benchmark exposure to asset-backed securities, commercial mortgage-backed securities and municipal bonds.
 
Overweights to government-credit and -agency securities.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class I Shares at NAV
   4.45%    2.50%    3.03%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 347,309,345
Holdings Count | Holding 268
Advisory Fees Paid, Amount $ 469,315
Investment Company Portfolio Turnover 305.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $347,309,345  
Total number of portfolio holdings
     268  
Portfolio turnover (%)
     305%  
Total management fees paid for the year
     $    469,315  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
C000205818 [Member]  
Shareholder Report [Line Items]  
Fund Name Nuveen Short Duration Impact Bond Fund
Class Name Class A Shares
Trading Symbol TSDBX
Annual or Semi-Annual Statement [Text Block] This annual shareholder report contains important information about the Class A Shares of the Nuveen Short Duration Impact Bond Fund for the period of April 1, 2025 to March 31, 2026.
Shareholder Report Annual or Semi-Annual annual shareholder report
Additional Information [Text Block] You can find additional information at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses. You can also request this information by contacting us at (800) 257‑8787.
Material Fund Change Notice [Text Block]
This report describes changes to the Fund that occurred during the reporting period.
Additional Information Phone Number (800) 257‑8787
Additional Information Website https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
Expenses [Text Block]
What were the Fund costs for the last year? (based on a hypothetical $10,000 investment)
   
   
Cost of a 
$10,000 investment 
  Costs paid as a percentage of
$10,000 investment*
     
Class A Shares
  $67    0.66%
* Annualized for period less than one year.
Expenses Paid, Amount $ 67
Expense Ratio, Percent 0.66% [59]
Factors Affecting Performance [Text Block]
How did the Fund perform last year? What affected the Fund’s performance?
Performance Highlights
 
The Nuveen Short Duration Impact Bond Fund returned 4.26% for Class A Shares at net asset value (NAV) for the 12 months ended March 31, 2026. The Fund outperformed the Bloomberg U.S. 1‑3 Year Government/Credit Bond Index, which returned 3.96%.
 
Top contributors to relative performance
 
An overweight position and security selection in corporate bonds.
 
Out‑of‑benchmark exposure to asset-backed securities, commercial mortgage-backed securities and municipal bonds.
 
Overweights to government-credit and -agency securities.
 
Top detractors from relative performance
 
Yield curve positioning in U.S. Treasuries.
Performance Past Does Not Indicate Future [Text] Performance data shown represents past performance and does not predict or guarantee future results.
Line Graph [Table Text Block]
LOGO
Average Annual Return [Table Text Block]
Average Annual Total Returns
     
     1‑Year    5‑Year    Since Inception
(11/16/18)
       
Class A Shares at NAV (excluding maximum sales charge)
   4.26%    2.27%    2.79%
       
Class A at maximum sales charge (Offering Price)
   1.64%    1.76%    2.43%
       
Bloomberg U.S. Aggregate Bond Index
   4.35%    0.31%    2.15%
       
Bloomberg U.S. 1‑3 Year Government/Credit Bond Index
   3.96%    2.04%    2.49%
Performance Inception Date Nov. 16, 2018
No Deduction of Taxes [Text Block] The graph and table do not reflect the deduction of taxes that a shareholder would pay on Fund distributions or redemption of Fund Shares.
Updated Performance Information Location [Text Block] For most recent month‑end performance, go to https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or call (800) 257‑8787.
Net Assets $ 347,309,345
Holdings Count | Holding 268
Advisory Fees Paid, Amount $ 469,315
Investment Company Portfolio Turnover 305.00%
Additional Fund Statistics [Text Block]
Fund Statistics (as of March 31, 2026)
Fund net assets
     $347,309,345  
Total number of portfolio holdings
     268  
Portfolio turnover (%)
     305%  
Total management fees paid for the year
     $    469,315  
Holdings [Text Block]
LOGO
LOGO
LOGO
(1) Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Credit Ratings Selection [Text Block] Credit quality ratings are based on the Bloomberg Barclays methodology, which uses the median rating of those compiled by the Moody’s, Standard & Poor’s and Fitch ratings agencies. If ratings are available from only two of these agencies, the lower rating is used. When only one rating is available, that one is used. These ratings are subject to change without notice.
Material Fund Change [Text Block]
How has the Fund changed?
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Summary of Change Legend [Text Block]
For more complete information, you may review the Fund’s next prospectus, which is expected to be available by August 1, 2026 at https://www.nuveen.com/en‑us/mutual‑funds/prospectuses or upon request at (800) 257‑8787.
Updated Prospectus Phone Number (800) 257‑8787
Updated Prospectus Web Address https://www.nuveen.com/en‑us/mutual‑funds/prospectuses
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