v3.25.2
Shareholder Report, Average Annual Return (Details)
 12 Months Ended 60 Months Ended 85 Months Ended 112 Months Ended 120 Months Ended
May 31, 2025
May 31, 2025
May 31, 2025
May 31, 2025
May 31, 2025
C000018356          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Large Cap Fund, Class A Shares        
C000018358          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Large Cap Disciplined Equity Fund, Class A Shares        
C000018357          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Large Cap Index Fund, Class A Shares        
C000134335          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index Fund, Class A Shares        
C000109763          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Extended Market Index Fund, Class A Shares        
C000018361          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Small Cap Fund, Class A Shares        
C000111997          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Small Cap II Fund, Class A Shares        
C000018359          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Small/Mid Cap Equity Fund, Class A Shares        
C000198133          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name U.S. Equity Factor Allocation Fund, Class A Shares        
C000036888          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name U.S. Managed Volatility Fund, Class A Shares        
C000160603          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Global Managed Volatility Fund, Class A Shares        
C000018354          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name World Equity Ex-US Fund, Class A Shares        
C000054521          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Screened World Equity Ex-US Fund, Class A Shares        
C000030145          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Emerging Markets Equity Fund, Class A Shares        
C000039813          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Opportunistic Income Fund, Class A Shares        
C000018355          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Core Fixed Income Fund, Class A Shares        
C000018352          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name High Yield Bond Fund, Class A Shares        
C000112815          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Long Duration Fund, Class A Shares        
C000018351          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Long Duration Credit Fund, Class A Shares        
C000096276          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Ultra Short Duration Bond Fund, Class A Shares        
C000018353          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Emerging Markets Debt Fund, Class A Shares        
C000036889          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Real Return Fund, Class A Shares        
C000144225          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Limited Duration Bond Fund, Class A Shares        
C000150792          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Intermediate Duration Credit Fund, Class A Shares        
C000081914          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Dynamic Asset Allocation Fund, Class A Shares        
C000102014          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Multi-Asset Real Return Fund, Class A Shares        
Without Sales Load [Member] | C000018356          
Average Annual Return [Line Items]          
Average Annual Return, Percent 12.92% 14.71%     10.50%
Without Sales Load [Member] | C000018358          
Average Annual Return [Line Items]          
Average Annual Return, Percent 13.18% 16.20%     11.63%
Without Sales Load [Member] | C000018357          
Average Annual Return [Line Items]          
Average Annual Return, Percent 13.57% 15.60%     12.53%
Without Sales Load [Member] | C000134335          
Average Annual Return [Line Items]          
Average Annual Return, Percent 13.45% 15.87%     12.81%
Without Sales Load [Member] | C000109763          
Average Annual Return [Line Items]          
Average Annual Return, Percent 9.88% 11.89%     8.90%
Without Sales Load [Member] | C000018361          
Average Annual Return [Line Items]          
Average Annual Return, Percent 3.57% 12.07%     6.82%
Without Sales Load [Member] | C000111997          
Average Annual Return [Line Items]          
Average Annual Return, Percent 0.67% 12.36%     7.36%
Without Sales Load [Member] | C000018359          
Average Annual Return [Line Items]          
Average Annual Return, Percent 1.24% 10.88%     6.74%
Without Sales Load [Member] | C000198133          
Average Annual Return [Line Items]          
Average Annual Return, Percent 15.71% 16.70% 13.12%    
Without Sales Load [Member] | C000036888          
Average Annual Return [Line Items]          
Average Annual Return, Percent 13.92% 11.55%     8.92%
Without Sales Load [Member] | C000160603          
Average Annual Return [Line Items]          
Average Annual Return, Percent 17.81% 11.87%   9.57%  
Without Sales Load [Member] | C000018354          
Average Annual Return [Line Items]          
Average Annual Return, Percent 14.92% 10.89%     5.99%
Without Sales Load [Member] | C000054521          
Average Annual Return [Line Items]          
Average Annual Return, Percent 14.67% 11.75%     7.64%
Without Sales Load [Member] | C000030145          
Average Annual Return [Line Items]          
Average Annual Return, Percent 11.47% 11.03%     5.51%
Without Sales Load [Member] | C000039813          
Average Annual Return [Line Items]          
Average Annual Return, Percent 7.06% 5.42%     3.94%
Without Sales Load [Member] | C000018355          
Average Annual Return [Line Items]          
Average Annual Return, Percent 5.90% (0.56%)     1.92%
Without Sales Load [Member] | C000018352          
Average Annual Return [Line Items]          
Average Annual Return, Percent 9.65% 7.70%     5.53%
Without Sales Load [Member] | C000112815          
Average Annual Return [Line Items]          
Average Annual Return, Percent 2.52% (4.04%)     1.95%
Without Sales Load [Member] | C000018351          
Average Annual Return [Line Items]          
Average Annual Return, Percent 2.60% (3.40%)     2.13%
Without Sales Load [Member] | C000096276          
Average Annual Return [Line Items]          
Average Annual Return, Percent 5.63% 2.87%     2.43%
Without Sales Load [Member] | C000018353          
Average Annual Return [Line Items]          
Average Annual Return, Percent 10.00% 3.11%     2.85%
Without Sales Load [Member] | C000036889          
Average Annual Return [Line Items]          
Average Annual Return, Percent 7.07% 3.64%     2.72%
Without Sales Load [Member] | C000144225          
Average Annual Return [Line Items]          
Average Annual Return, Percent 6.23% 2.08%     2.14%
Without Sales Load [Member] | C000150792          
Average Annual Return [Line Items]          
Average Annual Return, Percent 5.54% (0.11%)     2.45%
Without Sales Load [Member] | C000081914          
Average Annual Return [Line Items]          
Average Annual Return, Percent 15.83% 16.91%     12.47%
Without Sales Load [Member] | C000102014          
Average Annual Return [Line Items]          
Average Annual Return, Percent 4.17% 6.78%     2.71%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94% 13.74%    
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
MSCI ACWI ex USA Index (NR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI ACWI ex USA Index (NR) (USD)        
Average Annual Return, Percent 13.75% 10.37%   8.12%  
MSCI ACWI ex USA Index (NR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI ACWI ex USA Index (NR) (USD)        
Average Annual Return, Percent 13.75% 10.37%     5.47%
MSCI ACWI ex USA Index (NR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI ACWI ex USA Index (NR) (USD)        
Average Annual Return, Percent 13.75% 10.37%     5.47%
MSCI ACWI ex USA Index (NR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI ACWI ex USA Index (NR) (USD)        
Average Annual Return, Percent 13.75% 10.37%     5.47%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg Global Aggregate Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg Global Aggregate Index (USD)        
Average Annual Return, Percent 7.03% (1.35%)     0.94%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
S&P 500 Index (TR)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name S&P 500 Index (TR)        
Average Annual Return, Percent 13.52% 15.94%     12.86%
Bloomberg U.S. Aggregate Bond Index (TR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg U.S. Aggregate Bond Index (TR) (USD)        
Average Annual Return, Percent 5.46% (0.90%)     1.49%
Russell 1000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 1000 Index (USD)        
Average Annual Return, Percent 13.73% 15.66%     12.58%
Russell 1000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 1000 Index (USD)        
Average Annual Return, Percent 13.73% 15.66%     12.58%
Russell Small Cap Completeness Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell Small Cap Completeness Index (USD)        
Average Annual Return, Percent 10.09% 11.88%     8.86%
Russell 2000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 2000 Index (USD)        
Average Annual Return, Percent 1.19% 9.64%     6.64%
Russell 2000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 2000 Index (USD)        
Average Annual Return, Percent 1.19% 9.64%     6.64%
Russell 2500 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 2500 Index (USD)        
Average Annual Return, Percent 3.49% 11.07%     7.82%
Russell 3000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 3000 Index (USD)        
Average Annual Return, Percent 13.12% 15.34% 12.99%    
Russell 3000 Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Russell 3000 Index (USD)        
Average Annual Return, Percent 13.12% 15.34%     12.21%
MSCI USA Minimum Volatility (NR) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI USA Minimum Volatility (NR) (USD)        
Average Annual Return, Percent 14.50% 10.03%     9.98%
MSCI USA Minimum Volatility Index (75%)/Russell 3000 Value Index (25%)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI USA Minimum Volatility Index (75%)/Russell 3000 Value Index (25%)        
Average Annual Return, Percent 13.42% 11.27%     10.17%
MSCI World Index (Net) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI World Index (Net) (USD)        
Average Annual Return, Percent 13.72% 14.18%   12.11%  
MSCI World Minimum Volatility Index (Net) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI World Minimum Volatility Index (Net) (USD)        
Average Annual Return, Percent 17.20% 8.32%   8.52%  
MSCI EFM (Emerging+Frontier Markets) Index (Net) (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name MSCI EFM (Emerging+Frontier Markets) Index (Net) (USD)        
Average Annual Return, Percent 13.11% 7.08%     3.92%
ICE BofA USD 3-Month Deposit Offered Rate Constant Maturity Index          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name ICE BofA USD 3-Month Deposit Offered Rate Constant Maturity Index        
Average Annual Return, Percent 5.01% 2.77%     2.13%
ICE BofA U.S. High Yield Constrained Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name ICE BofA U.S. High Yield Constrained Index (USD)        
Average Annual Return, Percent 9.28% 5.81%     4.93%
70/30 Bloomberg U.S. Long Credit/U.S. Long Govt          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name 70/30 Bloomberg U.S. Long Credit/U.S. Long Govt        
Average Annual Return, Percent 2.06% (4.28%)     1.51%
Bloomberg Long A+ U.S. Credit Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg Long A+ U.S. Credit Index (USD)        
Average Annual Return, Percent 2.21% (3.60%)     1.81%
Bloomberg Short U.S. Treasury 9-12 Month Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg Short U.S. Treasury 9-12 Month Index (USD)        
Average Annual Return, Percent 5.03% 2.27%     1.91%
50/50 JPM EMBI Global Div & JPM GBI EM Global Div          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name 50/50 JPM EMBI Global Div & JPM GBI EM Global Div        
Average Annual Return, Percent 8.83% 1.75%     2.47%
Bloomberg 1-5 Year U.S. TIPS Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg 1-5 Year U.S. TIPS Index (USD)        
Average Annual Return, Percent 6.97% 3.66%     2.76%
ICE BofA 1-3 Year U.S. Treasury Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name ICE BofA 1-3 Year U.S. Treasury Index (USD)        
Average Annual Return, Percent 5.65% 1.25%     1.55%
Bloomberg A+ U.S. Credit Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg A+ U.S. Credit Index (USD)        
Average Annual Return, Percent 5.36% (0.52%)     2.07%
Bloomberg 1-5 Year U.S. TIPS Index (USD)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg 1-5 Year U.S. TIPS Index (USD)        
Average Annual Return, Percent 6.97% 3.66%     2.76%
Bloomberg 1-5 Year U.S. TIPS Index (70%)/Bloomberg Commodity Index Total Return Index (20%)/S&P 500 Index (10%)          
Average Annual Return [Line Items]          
Line Graph and Table Measure Name Bloomberg 1-5 Year U.S. TIPS Index (70%)/Bloomberg Commodity Index Total Return Index (20%)/S&P 500 Index (10%)        
Average Annual Return, Percent 6.68% 6.84%     3.82%