2.4.0.84020 - Disclosure - Acquisition (Details)truefalsefalse1false USDfalsefalseD2013Q1_M0204_CuprumAcquisitionMember_CustomerRelationshipsMemberhttp://www.sec.gov/CIK0001126328duration2013-02-03T00:00:002013-02-04T00:00:00USDStandardhttp://www.xbrl.org/2003/iso4217USDiso42170$1true 4pfg_BusinessAcquisitionAbstractpfg_falsenadurationfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1falsefalsefalse00falsefalsefalsexbrli:stringItemTypestringfalse0Business Acquisition2false 5pfg_OwnershipPercentageOfExistingPrincipalShareholderspfg_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.630.63falsefalsefalsenum:percentItemTypepureRepresents the ownership percentage of existing principal shareholders purchased via a public tender offer.No definition available.false0Percent of principal shareholders ownership acquired (as a percent)3false 5pfg_OwnershipPercentageOfPubliclyTradedSharespfg_falsenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.370.37falsefalsefalsenum:percentItemTypepureRepresents the percentage of publicly traded shares that could have potentially been purchased via a public tender offer.No definition available.false0Potential percent of publicly traded shares acquired (as a percent)4false 5us-gaap_BusinessAcquisitionPercentageOfVotingInterestsAcquiredus-gaap_truenainstantfalsefalsefalsefalsefalsefalsefalsefalseterseLabel1truetruefalse0.91550.9155falsefalsefalsenum:percentItemTypepurePercentage of voting equity interests acquired in the business combination.Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 141R -Paragraph 68 -Subparagraph c -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. 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