v3.26.1
Shareholder Report, Average Annual Return (Details)
8 Months Ended 12 Months Ended 60 Months Ended 68 Months Ended 120 Months Ended
May 31, 2026
May 31, 2026
May 31, 2026
May 31, 2026
May 31, 2026
C000014639 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   12.32% 4.25%   6.15%
C000047972 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   12.55% 4.51%   6.41%
C000079559 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   12.29% 4.33%   6.25%
C000162552 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   12.46% 4.44%   6.38%
C000162553 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   12.95% 4.53%   6.70%
C000079560 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   12.87% 4.46%   6.60%
C000047973 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   12.99% 4.62%   6.76%
C000014640 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   12.75% 4.36%   6.50%
C000014641 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   13.77% 4.70%   7.01%
C000047974 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   14.00% 4.96%   7.27%
C000079561 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   13.96% 4.81%   7.12%
C000162554 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   13.98% 4.89%   7.21%
C000162555 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   15.17% 5.34%   7.91%
C000079562 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   14.94% 5.23%   7.80%
C000047975 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   15.15% 5.38%   7.96%
C000014642 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   14.90% 5.12%   7.70%
C000014643 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   16.58% 5.81%   8.51%
C000047976 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   16.82% 6.08%   8.78%
C000079563 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   16.64% 5.90%   8.61%
C000162556 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   16.87% 6.03%   8.73%
C000162557 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   18.72% 6.79%   9.57%
C000079564 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   18.45% 6.69%   9.48%
C000047977 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   18.67% 6.86%   9.64%
C000014644 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   18.46% 6.60%   9.37%
C000014647 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   21.00% 7.63%   10.35%
C000047978 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   21.29% 7.91%   10.63%
C000079566 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   21.19% 7.74%   10.45%
C000162559 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   21.27% 7.84%   10.57%
C000033271 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   10.99% 4.65%   7.62%
C000033273 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   18.07% 6.17%   8.53%
C000033272 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   17.80% 5.90%   8.25%
C000054992 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   22.89% 8.29%   11.02%
C000054991 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   23.23% 8.56%   11.29%
C000079575 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   23.11% 8.41%   11.12%
C000162574 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   23.27% 8.51%   11.26%
C000162575 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   24.34% 8.86%   11.52%
C000079576 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   24.15% 8.74%   11.38%
C000054993 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   24.29% 8.90%   11.55%
C000054994 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   24.05% 8.64%   11.28%
C000054997 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   12.76% 4.33%   6.10%
C000054996 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   13.10% 4.60%   6.37%
C000079577 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   12.93% 4.44%   6.20%
C000162576 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   13.02% 4.52%   6.29%
C000054995 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   6.37% 3.12%   5.47%
C000162577 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   13.36% 4.68%   6.43%
C000079518 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   13.16% 4.58%   6.32%
C000079517 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   13.34% 4.74%   6.49%
C000079519 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   13.10% 4.48%   6.22%
C000079522 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   14.54% 4.92%   6.38%
C000079520 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   14.79% 5.18%   6.65%
C000079521 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   14.63% 5.02%   6.49%
C000162578 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   14.78% 5.09%   6.57%
C000162580 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   14.64% 5.16%   6.99%
C000079528 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   14.54% 5.06%   6.89%
C000079527 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   14.69% 5.23%   7.05%
C000079529 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   14.41% 4.96%   6.78%
C000079532 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   15.68% 5.43%   7.37%
C000079530 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   15.95% 5.69%   7.65%
C000079531 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   15.83% 5.54%   7.49%
C000162581 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   15.94% 5.61%   7.56%
C000162582 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   17.24% 6.15%   8.32%
C000079534 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   17.04% 6.07%   8.24%
C000079533 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   17.22% 6.23%   8.40%
C000079535 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   16.96% 5.97%   8.12%
C000079538 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   18.95% 6.76%   9.01%
C000079536 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   19.24% 7.03%   9.28%
C000079537 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   19.07% 6.87%   9.12%
C000162583 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   19.21% 6.96%   9.20%
C000162584 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   21.35% 7.88%   10.16%
C000079540 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   21.14% 7.78%   10.06%
C000079539 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   21.36% 7.96%   10.23%
C000079541 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   21.04% 7.68%   9.95%
C000079544 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   24.09% 8.92%   11.05%
C000079542 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   24.41% 9.19%   11.33%
C000079543 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   24.23% 9.02%   11.16%
C000162585 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   24.35% 9.12%   11.25%
C000162586 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   26.57% 9.92%   11.99%
C000079546 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   26.42% 9.84%   11.91%
C000079545 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   26.63% 10.00%   12.07%
C000079547 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   26.30% 9.72%   11.80%
C000079550 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   27.46% 10.10%   12.08%
C000079548 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   27.78% 10.38%   12.36%
C000079549 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   27.57% 10.21%   12.19%
C000162587 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   27.72% 10.29%   12.28%
C000162590 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   28.12% 10.44%   12.43%
C000099415 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   27.91% 10.36%   12.33%
C000099414 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   28.13% 10.51%   12.50%
C000099413 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   27.83% 10.24%   12.22%
C000099416 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   24.32% 8.75%   11.39%
C000099417 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   24.67% 9.02%   11.67%
C000099418 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   24.41% 8.86%   11.50%
C000162591 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   24.62% 8.98%   11.63%
C000107519 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   18.82% 7.88%   11.27%
C000162593 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   26.50% 9.41%   12.20%
C000107518 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   26.30% 9.33%   12.10%
C000107517 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   26.47% 9.49%   12.27%
C000107520 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   26.17% 9.22%   12.00%
C000107524 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   13.23% 4.50%   6.22%
C000107521 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   13.50% 4.74%   6.48%
C000107522 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   13.26% 4.58%   6.31%
C000162594 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   13.50% 4.67%   6.40%
C000107523 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   6.68% 3.23%   5.56%
C000107526 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   14.85% 6.24%   9.40%
C000162595 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   22.09% 7.72%   10.28%
C000107525 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   22.03% 7.67%   10.21%
C000107528 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   22.18% 7.80%   10.36%
C000107527 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   21.89% 7.54%   10.08%
C000107532 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   8.86% 3.12%   4.23%
C000107529 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   9.13% 3.36%   4.49%
C000107530 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   8.93% 3.23%   4.33%
C000162596 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   9.01% 3.29%   4.44%
C000107531 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   2.53% 1.87%   3.58%
C000107535 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at maximum sales charge (Offering Price)      
Average Annual Return, Percent   10.86% 4.53%   7.50%
C000162597 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   17.92% 5.99%   8.36%
C000107534 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   17.82% 5.93%   8.28%
C000107533 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   18.00% 6.08%   8.44%
C000107536 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   17.67% 5.81%   8.17%
C000145614 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   24.61% 8.86%   11.50%
C000145612 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   24.84% 9.13%   11.78%
C000145613 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   24.75% 8.96%   11.62%
C000162601 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   24.87% 9.07%   11.73%
C000162602 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   28.45% 10.58%   12.57%
C000145617 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   28.28% 10.50%   12.48%
C000145616 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   28.51% 10.66%   12.64%
C000145615 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   28.18% 10.39%   12.36%
C000221705 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   24.84% 9.07% 12.68%  
C000221704 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   25.14% 9.26% 12.91%  
C000221702 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   25.01% 9.07% 12.70%  
C000221703 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   25.04% 9.14% 12.77%  
C000221708 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent   28.72% 10.77% 14.08%  
C000221706 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent   28.60% 10.66% 13.98%  
C000221709 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent   28.82% 10.84% 14.14%  
C000221707 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent   28.46% 10.50% 13.81%  
C000263980 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent 12.20%        
C000263978 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent 12.37%        
C000263979 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent 12.23%        
C000263981 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent 12.23%        
C000263985 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class I Shares at NAV      
Average Annual Return, Percent 15.11%        
C000263983 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Premier Class Shares at NAV      
Average Annual Return, Percent 15.11%        
C000263982 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class R6 Shares at NAV      
Average Annual Return, Percent 15.15%        
C000263984 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Retirement Class Shares at NAV      
Average Annual Return, Percent 14.98%        
Without Sales Load [Member] | C000033271 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   17.77% 5.90%   8.25%
Without Sales Load [Member] | C000054995 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   12.84% 4.34%   6.10%
Without Sales Load [Member] | C000107519 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   26.07% 9.16%   11.93%
Without Sales Load [Member] | C000107523 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   13.19% 4.46%   6.19%
Without Sales Load [Member] | C000107526 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   21.85% 7.51%   10.05%
Without Sales Load [Member] | C000107531 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   8.81% 3.08%   4.20%
Without Sales Load [Member] | C000107535 [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Class A Shares at NAV (excluding maximum sales charge)      
Average Annual Return, Percent   17.62% 5.78%   8.14%
Russell 3000 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Russell 3000® Index      
Average Annual Return, Percent 13.88% 29.45% 12.92% 16.41% 15.12%
S And P Target Date 2010 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2010 Index      
Average Annual Return, Percent   12.87% 4.81%   6.04%
Lifecycle 2010 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2010 Fund Composite Index      
Average Annual Return, Percent   13.34% 4.78%   6.57%
Bloomberg U S Aggregate Bond Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Bloomberg U.S. Aggregate Bond Index      
Average Annual Return, Percent 1.48% 5.13% 0.17% (0.14%) 1.70%
Lifecycle 2015 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2015 Fund Composite Index      
Average Annual Return, Percent   14.66% 5.25%   7.13%
S and P Target Date 2015 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2015 Index      
Average Annual Return, Percent   13.81% 5.10%   6.55%
S And P Target Date 2020 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2020 Index      
Average Annual Return, Percent   14.70% 5.52%   7.05%
Lifecycle 2020 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2020 Fund Composite Index      
Average Annual Return, Percent   15.96% 5.74%   7.73%
Lifecycle 2025 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2025 Fund Composite Index      
Average Annual Return, Percent   17.26% 6.28%   8.49%
S And P Target Date 2025 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2025 Index      
Average Annual Return, Percent   16.73% 6.14%   7.91%
S And P Target Date 2030 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2030 Index      
Average Annual Return, Percent   19.00% 7.09%   8.88%
Lifecycle 2030 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2030 Fund Composite Index      
Average Annual Return, Percent   19.27% 7.08%   9.38%
Lifecycle 2035 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2035 Fund Composite Index      
Average Annual Return, Percent   21.38% 8.01%   10.32%
S And P Target Date 2035 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2035 Index      
Average Annual Return, Percent   21.69% 8.14%   9.92%
S And P Target Date 2040 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2040 Index      
Average Annual Return, Percent   24.41% 9.16%   10.78%
Lifecycle 2040 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2040 Fund Composite Index      
Average Annual Return, Percent   24.47% 9.26%   11.42%
Managed Allocation Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Managed Allocation Fund Composite Index      
Average Annual Return, Percent   20.02% 7.04%   8.88%
Morningstar Moderate Target Risk Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Morningstar Moderate Target Risk Index      
Average Annual Return, Percent   18.36% 6.16%   8.23%
S And P Target Date 2045 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2045 Index      
Average Annual Return, Percent   26.31% 9.86%   11.35%
Lifecycle 2045 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2045 Fund Composite Index      
Average Annual Return, Percent   26.69% 10.06%   12.17%
Lifecycle 2050 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2050 Fund Composite Index      
Average Annual Return, Percent   27.86% 10.44%   12.46%
S And P Target Date 2050 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2050 Index      
Average Annual Return, Percent   27.16% 10.15%   11.64%
S And P Target Date Retirement Income Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date Retirement Income Index      
Average Annual Return, Percent   12.59% 4.59%   5.47%
Lifecycle Retirement Income Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Retirement Income Fund Composite Index      
Average Annual Return, Percent   14.77% 5.22%   6.72%
Lifecycle Index 2010 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2010 Fund Composite Index      
Average Annual Return, Percent   13.48% 4.80%   6.57%
Lifecycle Index Retirement Income Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index Retirement Income Fund Composite Index      
Average Annual Return, Percent   14.92% 5.24%   6.72%
Lifecycle Index 2015 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2015 Fund Composite Index      
Average Annual Return, Percent   14.81% 5.28%   7.13%
Lifecycle Index 2020 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2020 Fund Composite Index      
Average Annual Return, Percent   16.10% 5.76%   7.73%
Lifecycle Index 2025 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2025 Fund Composite Index      
Average Annual Return, Percent   17.39% 6.30%   8.48%
Lifecycle Index 2030 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2030 Fund Composite Index      
Average Annual Return, Percent   19.39% 7.10%   9.37%
Lifecycle Index 2035 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2035 Fund Composite Index      
Average Annual Return, Percent   21.49% 8.03%   10.32%
Lifecycle Index 2040 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2040 Fund Composite Index      
Average Annual Return, Percent   24.57% 9.28%   11.42%
Lifecycle Index 2045 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2045 Fund Composite Index      
Average Annual Return, Percent   26.78% 10.08%   12.16%
Lifecycle Index 2050 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2050 Fund Composite Index      
Average Annual Return, Percent   27.93% 10.45%   12.44%
Lifecycle Index 2055 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2055 Fund Composite Index      
Average Annual Return, Percent   28.33% 10.61%   12.59%
S And P Target Date 2055 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2055 Index      
Average Annual Return, Percent   27.78% 10.31%   11.80%
Lifecycle 2055 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2055 Fund Composite Index      
Average Annual Return, Percent   28.26% 10.59%   12.61%
Lifestyle Aggressive Growth Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifestyle Aggressive Growth Fund Composite Index      
Average Annual Return, Percent   30.66% 11.55%   13.50%
Morningstar Aggressive Target Risk Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Morningstar Aggressive Target Risk Index      
Average Annual Return, Percent   26.15% 9.59%   11.75%
Morningstar Moderately Conservative Target Risk Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Morningstar Moderately Conservative Target Risk Index      
Average Annual Return, Percent   13.62% 4.35%   6.24%
Lifestyle Conservative Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifestyle Conservative Fund Composite Index      
Average Annual Return, Percent   14.62% 5.19%   6.61%
Lifestyle Growth Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifestyle Growth Fund Composite Index      
Average Annual Return, Percent   25.27% 9.30%   11.21%
Morningstar Moderately Aggressive Target Risk Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Morningstar Moderately Aggressive Target Risk Index      
Average Annual Return, Percent   22.67% 8.02%   10.23%
Morningstar Conservative Target Risk Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Morningstar Conservative Target Risk Index      
Average Annual Return, Percent   9.30% 2.20%   3.90%
Lifestyle Income Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifestyle Income Fund Composite Index      
Average Annual Return, Percent   9.38% 3.29%   4.29%
Lifestyle Moderate Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifestyle Moderate Fund Composite Index      
Average Annual Return, Percent   20.02% 7.04%   8.88%
S And P Target Date 2060 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2060 Index      
Average Annual Return, Percent   27.80% 10.31%   11.87%
Lifecycle 2060 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2060 Fund Composite Index      
Average Annual Return, Percent   28.59% 10.73%   12.75%
Lifecycle Index 2060 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2060 Fund Composite Index      
Average Annual Return, Percent   28.67% 10.75%   12.74%
S And P Target Date 2065 Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   S&P Target Date 2065+ Index      
Average Annual Return, Percent 15.02% 28.11% 10.50% 14.00%  
Lifecycle 2065 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2065 Fund Composite Index      
Average Annual Return, Percent   28.93% 10.87% 14.30%  
Lifecycle Index 2065 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2065 Fund Composite Index      
Average Annual Return, Percent   29.01% 10.89% 14.25%  
Lifecycle 2070 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle 2070 Fund Composite Index      
Average Annual Return, Percent 15.24%        
Lifecycle Index 2070 Fund Composite Index [Member]          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name   Lifecycle Index 2070 Fund Composite Index      
Average Annual Return, Percent 15.47%