Net Assets Investment Company, Portfolio Turnover C000095778 [Member] Empower S&P Small Cap 600® Index Fund - Class L C000155767 [Member] Empower S&P Small Cap 600® Index Fund - Institutional Class C000069818 [Member] Empower S&P Small Cap 600® Index Fund - Investor Class C000159791 [Member] Empower Small Cap Growth Fund - Institutional Class C000159789 [Member] Empower Small Cap Growth Fund - Investor Class C000155756 [Member] Empower Small Cap Value Fund - Institutional Class C000069806 [Member] Empower Small Cap Value Fund - Investor Class Investment Type [Axis] Financial Services Sector [Member] Consumer, Cyclical [Member] Consumer, Non-cyclical [Member] Energy Sector [Member] Technology Sector [Member] Government Money Market Mutual Funds [Member] Basic Materials [Member] Dreyfus Institutional Preferred Government Money Market Fund Institutional Class [Member] Moog Inc Class A [Member] Garrett Motion Inc [Member] Bel Fuse Inc Class B [Member] Kodiak Gas Services Inc [Member] Popular Inc [Member] TD SYNNEX Corp [Member] Ultra Clean Holdings Inc [Member] Ameris Bancorp [Member] Concentra Group Holdings Parent Inc [Member] Element Solutions Inc [Member] MACOM Technology Solutions Holdings Inc [Member] Mercury Systems Inc [Member] SPX Technologies Inc [Member] MYR Group Inc [Member] Legence Corp Class A [Member] TechnipFMC PLC [Member] Advanced Energy Industries Inc [Member] JFrog Ltd [Member] Short Term Investment [Member] Short Term Investments [Member] FormFactor Inc [Member] Viasat Inc [Member] Molina Healthcare Inc [Member] Argan Inc [Member] BrightSpring Health Services Inc [Member] MaxLinear Inc [Member] Krystal Biotech Inc [Member] ESCO Technologies Inc [Member]