Parametric Emerging Markets Fund Parametric Emerging Markets Fund Parametric International Equity Fund Parametric International Equity Fund Parametric Volatility Risk Premium - Defensive Fund Parametric Volatility Risk Premium - Defensive Fund Dcombinedparametricinternationalfundsprospectus_17513 Parametric International Funds Classess - A,C,I,R, & R6 Dparametricvolatilityriskpremiumdefensivefundprospectus_17521 Parametric Volatility Risk Premium - Defensive Fund Dcombinedparametricinternationalfundssai_17512 Combined Parametric International Funds SAI Dparametricvolatilityriskpremiumdefensivefundsai_17522 Parametric Volatility Risk Premium - Defensive Fund SAI Class A - C000034229 Class A Class C - C000034230 Class C Class I - C000034231 Class I Class R6 - C000142449 Class R6 Class A - C000086647 Class A Class I - C000086649 Class I Class R - C000161753 Class R Class R6 - C000161754 Class R6 Class I - C000177028 Class I Emerging Markets Investment Risk [Member] Emerging Markets Investment Risk [Member] Frontier Market Investment Risk [Member] Frontier Market Investment Risk [Member] China Region Risk [Member] China Region Risk [Member] MSCI Emerging Markets Index (reflects net dividends, which reflect the deduction of withholding taxes) MSCI Emerging Markets Index (reflects net dividends, which reflect the deduction of withholding taxes) Market Risk [Member] Market Risk [Member] Equity Securities Risk [Member] Equity Securities Risk [Member] Foreign Investment Risk [Member] Foreign Investment Risk [Member] Currency Risk [Member] Currency Risk [Member] Smaller Company Risk [Member] Smaller Company Risk [Member] ETF Risk [Member] ETF Risk [Member] Liquidity Risk [Member] Liquidity Risk [Member] Real Estate Risk [Member] Real Estate Risk [Member] Rules-Based Management Risks [Member] Rules-Based Management Risks [Member] Securities Lending Risk [Member] Securities Lending Risk [Member] Focused Investment Risk [Member] Focused Investment Risk [Member] Geographic Risk [Member] Geographic Risk [Member] General Fund Investing Risks [Member] General Fund Investing Risks [Member] MSCI EAFE Index (reflects net dividends, which reflect the deduction of withholding taxes) MSCI EAFE Index (reflects net dividends, which reflect the deduction of withholding taxes) Option Strategy Risk Option Strategy Risk S&P 500 Index Risk S&P 500 Index Risk Derivatives Risk [Member] Derivatives Risk [Member] Leverage Risk [Member] Leverage Risk [Member] U.S. Treasury Securities U.S. Treasury Securities Money Market Instrument Risk [Member] Money Market Instrument Risk [Member] Interest Rate Risk [Member] Interest Rate Risk [Member] Credit Risk [Member] Credit Risk [Member] Tax Risk [Member] Tax Risk [Member] S&P 500 Index (reflects no deduction for fees, expenses or taxes) S&P 500 Index (reflects no deduction for fees, expenses or taxes) Cboe S&P 500 BuyWrite Index (reflects no deduction for fees, expenses or taxes) Cboe S&P 500 BuyWrite Index (reflects no deduction for fees, expenses or taxes) ICE BofAML 3-Month U.S. Treasury Bill Index (reflects no deduction for fees, expenses or taxes) ICE BofAML 3-Month U.S. Treasury Bill Index (reflects no deduction for fees, expenses or taxes) Blended Index (reflects no deduction for fees, expenses or taxes) Blended Index (reflects no deduction for fees, expenses or taxes)