3.24.0.1 html 162 84 1 true 71 0 false 2 false false R1.htm 000000 - Document - Document and Entity Information {Elements} Sheet http://www.nuveen.com/role/DocumentDocumentandEntityInformationElements000000 Document and Entity Information Risk/Return 1 false false R2.htm 000021 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Dividend Value Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenDividendValueFund000021 Risk/Return Detail Data- Nuveen Dividend Value Fund Risk/Return 2 false false R3.htm 000041 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Large Cap Select Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenLargeCapSelectFund000041 Risk/Return Detail Data- Nuveen Large Cap Select Fund Risk/Return 3 false false R4.htm 000061 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Mid Cap Growth Opportunities Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenMidCapGrowthOpportunitiesFund000061 Risk/Return Detail Data- Nuveen Mid Cap Growth Opportunities Fund Risk/Return 4 false false R5.htm 000081 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Mid Cap Value Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenMidCapValueFund000081 Risk/Return Detail Data- Nuveen Mid Cap Value Fund Risk/Return 5 false false R6.htm 000101 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Small Cap Growth Opportunities Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenSmallCapGrowthOpportunitiesFund000101 Risk/Return Detail Data- Nuveen Small Cap Growth Opportunities Fund Risk/Return 6 false false R7.htm 000121 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Small Cap Select Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenSmallCapSelectFund000121 Risk/Return Detail Data- Nuveen Small Cap Select Fund Risk/Return 7 false false R8.htm 000141 - Disclosure - Risk/Return Detail Data {Elements} - Nuveen Small Cap Value Fund Sheet http://www.nuveen.com/role/DisclosureRiskReturnDetailDataElementsNuveenSmallCapValueFund000141 Risk/Return Detail Data- Nuveen Small Cap Value Fund Risk/Return 8 false false All Reports Book All Reports d744145d485bpos.htm nifi-20240228.xsd nifi-20240228_cal.xml nifi-20240228_def.xml nifi-20240228_lab.xml nifi-20240228_pre.xml g744145img_0cf9119a3c0a4.jpg g744145img_2f21dcae25bf4.jpg g744145img_7e7680259f8f4.jpg g744145img_867d2ec694ac4.jpg g744145img_8d92cc9583304.jpg g744145img_9e52c5289b6c4.jpg g744145img_bdb26a978d344.jpg g744145img_e2c691f24cc54.jpg http://xbrl.sec.gov/dei/2023 http://xbrl.sec.gov/rr/2023 true true