Investor Class Shares SA U.S. Fixed Income Fund Market Risk [Member] Interest Rate and Related Risks [Member] Inflation-Protected Securities Interest Rate Risk [Member] Inflation-Protected Securities Tax Risk [Member] Risks of Investing for Inflation Protection [Member] Credit Risk [Member] Income Risk [Member] Call Risk [Member] Investment Grade Securities Risk [Member] U.S. Government Securities Risk [Member] Sector Risk [Member] Banking Concentration Risk [Member] Financials Sector Risk [Member] European Economic Risk [Member] Foreign Government and Supranational Organization Obligations Risk [Member Foreign Securities Risk [Member] Liquidity Risk [Member] Operational Risk [Member] Cybersecurity Risk [Member] Management Risk [Member] Large Investor Risk [Member] SA Global Fixed Income Fund Foreign Securities and Currency Risk [Member] Hedging Risk [Member] Securities Lending Risk [Member] SA U.S. Core Market Fund Large Company Stock Risk [Member] Medium-Size Company Stock Risk [Member] Small Company Stock Risk [Member] Information Technology Sector Risk [Member] Profitability Investment Risk [Member] Derivatives Risk [Member] SA U.S. Value Fund Value Stock Risk [Member] SA U.S. Small Company Fund Industrial Sector Risk [Member] SA International Value Fund Japan Risk [Member] U.S. Trade Policy Risk [Member] SA International Small Company Fund Fund of Funds Risk [Member] Geographic Focus Risk [Member] SA Emerging Markets Value Fund Emerging Markets Risk [Member] China Investments Risk [Member] Indian Market and India Region Risk [Member] Taiwan Investments Risk [Member] SA Real Estate Securities Fund Risk of Concentrating in the Real Estate Industry [Member] Real Estate and REIT Investment Risk [Member] Interest Rate Risk [Member] Cyclical Market Risk [Member] SA Worldwide Moderately Aggressive Fund Investor Class Shares SA Worldwide Moderately Aggressive Fund Affiliated Fund Risk [Member] Investment in Underlying SA Funds Risk [Member] Allocation Risk [Member] Equity Risk [Member] Capitalization Risk [Member] SA U.S. Fixed Income Fund SA Global Fixed Income Fund SA U.S. Core Market Fund SA U.S. Value Fund SA U.S. Small Company Fund SA International Value Fund SA International Small Company Fund SA Emerging Markets Value Fund SA Real Estate Securities Fund SA Worldwide Moderately Aggressive Fund Morningstar® Emerging Markets All Cap Target Market Exposure Index Morningstar® Emerging Markets Value Target Market Exposure Index Morningstar® US Core Bond Index Morningstar® US 1-3 Yr Composite Government and Corporate Bond Index Morningstar® Global Core Bond Hedged Index Morningstar® Global 1-5 Yr Treasury Bond Hedged Index Morningstar® US Market Extended Index Morningstar® US Large-Mid Cap Broad Value Index Morningstar® US Small Cap Extended Index Morningstar® Developed Markets ex-US All Cap Target Market Exposure Index Morningstar® Developed Markets ex-US Value Target Market Exposure Index Morningstar® Developed Markets ex-US Small-Cap Target Market Exposure Index Morningstar® US REIT Index Morningstar® Global Markets Index Morningstar® US Moderate Target Allocation Index SA U.S. Fixed Income Fund [Default Label] SA Global Fixed Income Fund [Default Label] SA U.S. Core Market Fund [Default Label] SA U.S. Value Fund [Default Label] SA U.S. Small Company Fund [Default Label] SA International Value Fund [Default Label] SA International Small Company Fund [Default Label] SA Emerging Markets Value Fund [Default Label] SA Real Estate Securities Fund [Default Label] SA Worldwide Moderately Aggressive Fund [Default Label]