Label	Element	Value
CornerCap Small-Cap Value Fund
Risk/Return:	rr_RiskReturnAbstract
Risk/Return [Heading]	rr_RiskReturnHeading	CornerCap Small-Cap Value Fund
Strategy [Heading]	rr_StrategyHeading	Principal Investment Strategies
Strategy Narrative [Text Block]	rr_StrategyNarrativeTextBlock	The Small-Cap Value Fund normally invests more than 80% of its net assets (including borrowings for investment, if any) in equity securities of small-cap U.S. companies. The Adviser defines small-cap companies as those companies with market capitalizations within the range of the Russell 2000® Index at the time of purchase. The market capitalization range of the Russell 2000® Index was $6.4 million to $10.8 billion as of March 31, 2017, and is expected to change frequently. Under normal circumstances, the Fund will be invested in common stocks that the Adviser believes are attractively valued relative to their growth potential, or undervalued in the market. The Adviser uses Fundametrics®, the Adviser’s proprietary quantitative research system, to select stocks for the Small-Cap Value Fund. Fundametrics® evaluates all stocks in the Fund’s investible universe with respect to over 120 fundamental factors. Fundametrics® was designed to evaluate stocks on many of the same criteria used by a human analyst, but is done using a systematic approach that minimizes human emotion and bias. Buy and sell decisions are determined by a subset of factors contained within the Fundametrics® "Alpha Composite" and "Financial Warnings Overlay". The Alpha Composite is a combination of alpha seeking factors designed to identify stocks with potential for excess returns. The makeup of the Alpha Composite is primarily valuation-focused factors, but also includes certain growth, momentum and other factors with low correlations to value for diversification purposes. The Financial Warnings Overlay is then applied to the Fund's investible universe of stocks using a separate set of risk factors designed to identify stocks with risk levels that the Adviser believes will lead to under performance. The Financial Warnings Overlay is designed to avoid high risk stocks that otherwise have attractive valuation metrics. Potential "buy" stocks - those that score highly with respect to the Alpha Composite and pass the Financial Warnings Overlay - are then evaluated with respect to whether they would improve portfolio diversification. The Small-Cap Value Fund typically sells stocks that score low on the Alpha Composite or are flagged by the Financial Warnings Overlay as presenting unreasonable risk. The Fund will sell securities when the Adviser determines that it is advantageous to do so, such as when securities with relatively greater value are available for purchase by the Fund, or to raise cash.
Strategy Portfolio Concentration [Text]	rr_StrategyPortfolioConcentration	The Small-Cap Value Fund normally invests more than 80% of its net assets (including borrowings for investment, if any) in equity securities of small-cap U.S. companies.

Label

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Value

Risk/Return:

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Risk/Return [Heading]

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CornerCap Small-Cap Value Fund

Strategy [Heading]

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Principal Investment Strategies

Strategy Narrative [Text Block]

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The Small-Cap Value Fund normally invests more than 80% of its net assets (including borrowings for investment, if any) in equity securities of small-cap U.S. companies. The Adviser defines small-cap companies as those companies with market capitalizations within the range of the Russell 2000® Index at the time of purchase. The market capitalization range of the Russell 2000® Index was $6.4 million to $10.8 billion as of March 31, 2017, and is expected to change frequently. Under normal circumstances, the Fund will be invested in common stocks that the Adviser believes are attractively valued relative to their growth potential, or undervalued in the market. The Adviser uses Fundametrics®, the Adviser’s proprietary quantitative research system, to select stocks for the Small-Cap Value Fund. Fundametrics® evaluates all stocks in the Fund’s investible universe with respect to over 120 fundamental factors. Fundametrics® was designed to evaluate stocks on many of the same criteria used by a human analyst, but is done using a systematic approach that minimizes human emotion and bias.

Buy and sell decisions are determined by a subset of factors contained within the Fundametrics® "Alpha Composite" and "Financial Warnings Overlay". The Alpha Composite is a combination of alpha seeking factors designed to identify stocks with potential for excess returns. The makeup of the Alpha Composite is primarily valuation-focused factors, but also includes certain growth, momentum and other factors with low correlations to value for diversification purposes. The Financial Warnings Overlay is then applied to the Fund's investible universe of stocks using a separate set of risk factors designed to identify stocks with risk levels that the Adviser believes will lead to under performance. The Financial Warnings Overlay is designed to avoid high risk stocks that otherwise have attractive valuation metrics. Potential "buy" stocks - those that score highly with respect to the Alpha Composite and pass the Financial Warnings Overlay - are then evaluated with respect to whether they would improve portfolio diversification. The Small-Cap Value Fund typically sells stocks that score low on the Alpha Composite or are flagged by the Financial Warnings Overlay as presenting unreasonable risk.

The Fund will sell securities when the Adviser determines that it is advantageous to do so, such as when securities with relatively greater value are available for purchase by the Fund, or to raise cash.

Strategy Portfolio Concentration [Text]

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The Small-Cap Value Fund normally invests more than 80% of its net assets (including borrowings for investment, if any) in equity securities of small-cap U.S. companies.