2.4.0.84056 - Disclosure - Derivative Financial Instruments (Details)truefalseIn Millions, unless otherwise specifiedfalse1false USDfalsefalse$D2013Q2YTD_InterestRateSwapMemberhttp://www.sec.gov/CIK0001126328duration2013-01-01T00:00:002013-06-30T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$2false USDfalsefalse$I2012_InterestRateSwapMemberhttp://www.sec.gov/CIK0001126328instant2012-12-31T00:00:000001-01-01T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170USDUSD$1true 3us-gaap_DerivativeLineItemsus-gaap_truenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalse2falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Derivative Financial Instruments, exposure2false 4pfg_AnnuitiesWithGuaranteedMinimumWithdrawalBenefitsMinimumAccountBalanceToMakeWithdrawalspfg_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse00USD$falsetruefalse2falsefalsefalse00falsefalsefalsexbrli:monetaryItemTypemonetaryRepresents the minimum account balance to make withdrawals by customer under the variable annuities with guaranteed minimum withdrawal benefits.No definition available.false2GMWB minimum account balance to make withdrawals by customer3false 4pfg_DerivativeCollateralPledgedpfg_falsedebitinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse407600000407.6USD$falsefalsefalse2truefalsefalse296900000296.9USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe carrying value as of the balance sheet date of the cash and securities pledged as collateral associated with derivative credit support agreements.No definition available.false2Cash and securities posted under collateral arrangements associated with derivative credit support agreements4false 4us-gaap_DerivativeNetLiabilityPositionAggregateFairValueus-gaap_truecreditinstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truefalsefalse11196000001119.6USD$falsefalsefalse2truefalsefalse12054000001205.4USD$falsefalsefalsexbrli:monetaryItemTypemonetaryThe aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4H -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624258-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44D -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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