2.4.0.6 Html 97 13 1 false 112 0 false 0 false false R1.htm 0011 - Document - Document And Entity Information {Elements} Sheet http://www.principalfunds.com/20120914/role/DocumentDocumentandEntityInformation Document And Entity Information false false R2.htm 010005 - Document - Risk/Return Summary {Unlabeled} (LargeCap Growth Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007015Member Risk/Return Summary (LargeCap Growth Fund (Prospectus Summary):) false false R3.htm 040000 - Disclosure - Risk/Return Detail Data {Elements} Sheet http://xbrl.sec.gov/rr/role/RiskReturnDetailData Risk/Return Detail Data false false R4.htm 050005 - Document - Risk/Return Summary {Unlabeled} (LargeCap Value Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007017Member Risk/Return Summary (LargeCap Value Fund (Prospectus Summary):) false false R5.htm 050040 - Disclosure - Risk/Return Detail Data {Elements} (LargeCap Value Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007017Member Risk/Return Detail Data (LargeCap Value Fund (Prospectus Summary):) false false R6.htm 050045 - Document - Risk/Return Summary {Unlabeled} (MidCap Blend Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007075Member Risk/Return Summary (MidCap Blend Fund (Prospectus Summary):) false false R7.htm 050080 - Disclosure - Risk/Return Detail Data {Elements} (MidCap Blend Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007075Member Risk/Return Detail Data (MidCap Blend Fund (Prospectus Summary):) false false R8.htm 050085 - Document - Risk/Return Summary {Unlabeled} (LargeCap Growth Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007077Member Risk/Return Summary (LargeCap Growth Fund I (Prospectus Summary):) false false R9.htm 050120 - Disclosure - Risk/Return Detail Data {Elements} (LargeCap Growth Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007077Member Risk/Return Detail Data (LargeCap Growth Fund I (Prospectus Summary):) false false R10.htm 050125 - Document - Risk/Return Summary {Unlabeled} (MidCap Growth Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007078Member Risk/Return Summary (MidCap Growth Fund (Prospectus Summary):) false false R11.htm 050160 - Disclosure - Risk/Return Detail Data {Elements} (MidCap Growth Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007078Member Risk/Return Detail Data (MidCap Growth Fund (Prospectus Summary):) false false R12.htm 050165 - Document - Risk/Return Summary {Unlabeled} (MidCap Value Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007080Member Risk/Return Summary (MidCap Value Fund III (Prospectus Summary):) false false R13.htm 050200 - Disclosure - Risk/Return Detail Data {Elements} (MidCap Value Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007080Member Risk/Return Detail Data (MidCap Value Fund III (Prospectus Summary):) false false R14.htm 050205 - Document - Risk/Return Summary {Unlabeled} (LargeCap Growth Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007121Member Risk/Return Summary (LargeCap Growth Fund II (Prospectus Summary):) false false R15.htm 050240 - Disclosure - Risk/Return Detail Data {Elements} (LargeCap Growth Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007121Member Risk/Return Detail Data (LargeCap Growth Fund II (Prospectus Summary):) false false R16.htm 050245 - Document - Risk/Return Summary {Unlabeled} (LargeCap Value Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007122Member Risk/Return Summary (LargeCap Value Fund III (Prospectus Summary):) false false R17.htm 050280 - Disclosure - Risk/Return Detail Data {Elements} (LargeCap Value Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007122Member Risk/Return Detail Data (LargeCap Value Fund III (Prospectus Summary):) false false R18.htm 050285 - Document - Risk/Return Summary {Unlabeled} (LargeCap Value Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007123Member Risk/Return Summary (LargeCap Value Fund I (Prospectus Summary):) false false R19.htm 050320 - Disclosure - Risk/Return Detail Data {Elements} (LargeCap Value Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007123Member Risk/Return Detail Data (LargeCap Value Fund I (Prospectus Summary):) false false R20.htm 050325 - Document - Risk/Return Summary {Unlabeled} (MidCap Growth Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007125Member Risk/Return Summary (MidCap Growth Fund III (Prospectus Summary):) false false R21.htm 050360 - Disclosure - Risk/Return Detail Data {Elements} (MidCap Growth Fund III (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007125Member Risk/Return Detail Data (MidCap Growth Fund III (Prospectus Summary):) false false R22.htm 050365 - Document - Risk/Return Summary {Unlabeled} (SmallCap Value Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007169Member Risk/Return Summary (SmallCap Value Fund II (Prospectus Summary):) false false R23.htm 050400 - Disclosure - Risk/Return Detail Data {Elements} (SmallCap Value Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007169Member Risk/Return Detail Data (SmallCap Value Fund II (Prospectus Summary):) false false R24.htm 050405 - Document - Risk/Return Summary {Unlabeled} (MidCap Value Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007173Member Risk/Return Summary (MidCap Value Fund I (Prospectus Summary):) false false R25.htm 050440 - Disclosure - Risk/Return Detail Data {Elements} (MidCap Value Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007173Member Risk/Return Detail Data (MidCap Value Fund I (Prospectus Summary):) false false R26.htm 050445 - Document - Risk/Return Summary {Unlabeled} (SmallCap Growth Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007175Member Risk/Return Summary (SmallCap Growth Fund I (Prospectus Summary):) false false R27.htm 050480 - Disclosure - Risk/Return Detail Data {Elements} (SmallCap Growth Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007175Member Risk/Return Detail Data (SmallCap Growth Fund I (Prospectus Summary):) false false R28.htm 050485 - Document - Risk/Return Summary {Unlabeled} (SmallCap Growth Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007176Member Risk/Return Summary (SmallCap Growth Fund II (Prospectus Summary):) false false R29.htm 050520 - Disclosure - Risk/Return Detail Data {Elements} (SmallCap Growth Fund II (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007176Member Risk/Return Detail Data (SmallCap Growth Fund II (Prospectus Summary):) false false R30.htm 050525 - Document - Risk/Return Summary {Unlabeled} (SmallCap Blend Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000007214Member Risk/Return Summary (SmallCap Blend Fund (Prospectus Summary):) false false R31.htm 050560 - Disclosure - Risk/Return Detail Data {Elements} (SmallCap Blend Fund (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000007214Member Risk/Return Detail Data (SmallCap Blend Fund (Prospectus Summary):) false false R32.htm 050565 - Document - Risk/Return Summary {Unlabeled} (Equity Income Fund formerly Equity Income Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturn_P0001-S000014240Member Risk/Return Summary (Equity Income Fund formerly Equity Income Fund I (Prospectus Summary):) false false R33.htm 050600 - Disclosure - Risk/Return Detail Data {Elements} (Equity Income Fund formerly Equity Income Fund I (Prospectus Summary):) Sheet http://www.principalfunds.com/20120914/role/RiskReturnDetailData_P0001-S000014240Member Risk/Return Detail Data (Equity Income Fund formerly Equity Income Fund I (Prospectus Summary):) true false All Reports Book All Reports ck0000898745-20120914.xml ck0000898745-20120914.xsd ck0000898745-20120914_def.xml ck0000898745-20120914_lab.xml ck0000898745-20120914_pre.xml ck0000898745-20120914_cal.xml true false