2.4.0.6 Html 813 577 1 false 179 0 false 5 false false R1.htm 0000 - Document - Document and Entity Information Sheet http://principal.com/role/DocumentAndEntityInformation Document and Entity Information true false R2.htm 0010 - Statement - Consolidated Statements of Financial Position Sheet http://principal.com/role/BalanceSheet Consolidated Statements of Financial Position false false R3.htm 0015 - Statement - Consolidated Statements of Financial Position (Parenthetical) Sheet http://principal.com/role/BalanceSheetParenthetical Consolidated Statements of Financial Position (Parenthetical) false false R4.htm 0020 - Statement - Consolidated Statements of Operations Sheet http://principal.com/role/StatementOfIncome Consolidated Statements of Operations false false R5.htm 0030 - Statement - Consolidated Statements of Comprehensive Income Sheet http://principal.com/role/StatementOfComprehensiveIncome Consolidated Statements of Comprehensive Income false false R6.htm 0040 - Statement - Consolidated Statements of Stockholders' Equity Sheet http://principal.com/role/StatementOfStockholdersEquity Consolidated Statements of Stockholders' Equity false false R7.htm 0045 - Statement - Consolidated Statements of Stockholders' Equity (Parenthetical) Sheet http://principal.com/role/StatementOfStockholdersEquityParenthetical Consolidated Statements of Stockholders' Equity (Parenthetical) false false R8.htm 0050 - Statement - Consolidated Statements of Cash Flows Sheet http://principal.com/role/CashFlows Consolidated Statements of Cash Flows false false R9.htm 1010 - Disclosure - Nature of Operations and Significant Accounting Policies Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPolicies Nature of Operations and Significant Accounting Policies false false R10.htm 1020 - Disclosure - Acquisition Sheet http://principal.com/role/DisclosureAcquisition Acquisition false false R11.htm 1030 - Disclosure - Variable Interest Entities Sheet http://principal.com/role/DisclosureVariableInterestEntities Variable Interest Entities false false R12.htm 1040 - Disclosure - Investments Sheet http://principal.com/role/DisclosureInvestments Investments false false R13.htm 1050 - Disclosure - Derivative Financial Instruments Sheet http://principal.com/role/DisclosureDerivativeFinancialInstruments Derivative Financial Instruments false false R14.htm 1060 - Disclosure - Income Taxes Sheet http://principal.com/role/DisclosureIncomeTaxes Income Taxes false false R15.htm 1070 - Disclosure - Employee and Agent Benefits Sheet http://principal.com/role/DisclosureEmployeeAndAgentBenefits Employee and Agent Benefits false false R16.htm 1080 - Disclosure - Contingencies, Guarantees and Indemnifications Sheet http://principal.com/role/DisclosureContingenciesGuaranteesAndIndemnifications Contingencies, Guarantees and Indemnifications false false R17.htm 1090 - Disclosure - Stockholders' Equity Sheet http://principal.com/role/DisclosureStockholdersEquity Stockholders' Equity false false R18.htm 1100 - Disclosure - Fair Value Measurements Sheet http://principal.com/role/DisclosureFairValueMeasurements Fair Value Measurements false false R19.htm 1110 - Disclosure - Segment Information Sheet http://principal.com/role/DisclosureSegmentInformation Segment Information false false R20.htm 1120 - Disclosure - Stock-Based Compensation Plans Sheet http://principal.com/role/DisclosureStockBasedCompensationPlans Stock-Based Compensation Plans false false R21.htm 1130 - Disclosure - Earnings Per Common Share Sheet http://principal.com/role/DisclosureEarningsPerCommonShare Earnings Per Common Share false false R22.htm 1140 - Disclosure - Condensed Consolidating Financial Information Sheet http://principal.com/role/DisclosureFinancialInformation Condensed Consolidating Financial Information false false R23.htm 2010 - Disclosure - Nature of Operations and Significant Accounting Policies (Policies) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesPolicies Nature of Operations and Significant Accounting Policies (Policies) false false R24.htm 3010 - Disclosure - Nature of Operations and Significant Accounting Policies (Tables) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesTables Nature of Operations and Significant Accounting Policies (Tables) false false R25.htm 3020 - Disclosure - Acquisition (Tables) Sheet http://principal.com/role/DisclosureAcquisitionTables Acquisition (Tables) false false R26.htm 3030 - Disclosure - Variable Interest Entities (Tables) Sheet http://principal.com/role/DisclosureVariableInterestEntitiesTables Variable Interest Entities (Tables) false false R27.htm 3040 - Disclosure - Investments (Tables) Sheet http://principal.com/role/DisclosureInvestmentsTables Investments (Tables) false false R28.htm 3050 - Disclosure - Derivative Financial Instruments (Tables) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsTables Derivative Financial Instruments (Tables) false false R29.htm 3070 - Disclosure - Employee and Agent Benefits (Tables) Sheet http://principal.com/role/DisclosureEmployeeAndAgentBenefitsTables Employee and Agent Benefits (Tables) false false R30.htm 3090 - Disclosure - Stockholders' Equity (Tables) Sheet http://principal.com/role/DisclosureStockholdersEquityTables Stockholders' Equity (Tables) false false R31.htm 3100 - Disclosure - Fair Value Measurements (Tables) Sheet http://principal.com/role/DisclosureFairValueMeasurementsTables Fair Value Measurements (Tables) false false R32.htm 3110 - Disclosure - Segment Information (Tables) Sheet http://principal.com/role/DisclosureSegmentInformationTables Segment Information (Tables) false false R33.htm 3120 - Disclosure - Stock-Based Compensation Plans (Tables) Sheet http://principal.com/role/DisclosureStockBasedCompensationPlansTables Stock-Based Compensation Plans (Tables) false false R34.htm 3130 - Disclosure - Earnings Per Common Share (Tables) Sheet http://principal.com/role/DisclosureEarningsPerCommonShareTables Earnings Per Common Share (Tables) false false R35.htm 3140 - Disclosure - Condensed Consolidating Financial Information (Tables) Sheet http://principal.com/role/DisclosureFinancialInformationTables Condensed Consolidating Financial Information (Tables) false false R36.htm 4010 - Disclosure - Nature of Operations and Significant Accounting Policies (Details) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesDetails Nature of Operations and Significant Accounting Policies (Details) false false R37.htm 4011 - Disclosure - Nature of Operations and Significant Accounting Policies (Details 2) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesDetails2 Nature of Operations and Significant Accounting Policies (Details 2) false false R38.htm 4012 - Disclosure - Nature of Operations and Significant Accounting Policies (Details 3) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesDetails3 Nature of Operations and Significant Accounting Policies (Details 3) false false R39.htm 4013 - Disclosure - Nature of Operations and Significant Accounting Policies (Details 4) Sheet http://principal.com/role/DisclosureNatureOfOperationsAndSignificantAccountingPoliciesDetails4 Nature of Operations and Significant Accounting Policies (Details 4) false false R40.htm 4020 - Disclosure - Acquisition (Details) Sheet http://principal.com/role/DisclosureAcquisitionDetails Acquisition (Details) false false R41.htm 4021 - Disclosure - Acquisition (Details 2) Sheet http://principal.com/role/DisclosureAcquisitionDetails2 Acquisition (Details 2) false false R42.htm 4022 - Disclosure - Acquisition (Details 3) Sheet http://principal.com/role/DisclosureAcquisitionDetails3 Acquisition (Details 3) false false R43.htm 4030 - Disclosure - Variable Interest Entities (Details) Sheet http://principal.com/role/DisclosureVariableInterestEntitiesDetails Variable Interest Entities (Details) false false R44.htm 4031 - Disclosure - Variable Interest Entities (Details 2) Sheet http://principal.com/role/DisclosureVariableInterestEntitiesDetails2 Variable Interest Entities (Details 2) false false R45.htm 4040 - Disclosure - Investments (Details) Sheet http://principal.com/role/DisclosureInvestmentsDetails Investments (Details) false false R46.htm 4041 - Disclosure - Investments (Details 2) Sheet http://principal.com/role/DisclosureInvestmentsDetails2 Investments (Details 2) false false R47.htm 4042 - Disclosure - Investments (Details 3) Sheet http://principal.com/role/DisclosureInvestmentsDetails3 Investments (Details 3) false false R48.htm 4043 - Disclosure - Investments (Details 4) Sheet http://principal.com/role/DisclosureInvestmentsDetails4 Investments (Details 4) false false R49.htm 4044 - Disclosure - Investments (Details 5) Sheet http://principal.com/role/DisclosureInvestmentsDetails5 Investments (Details 5) false false R50.htm 4045 - Disclosure - Investments (Details 6) Sheet http://principal.com/role/DisclosureInvestmentsDetails6 Investments (Details 6) false false R51.htm 4046 - Disclosure - Investments (Details 7) Sheet http://principal.com/role/DisclosureInvestmentsDetails7 Investments (Details 7) false false R52.htm 4047 - Disclosure - Investments (Details 8) Sheet http://principal.com/role/DisclosureInvestmentsDetails8 Investments (Details 8) false false R53.htm 4048 - Disclosure - Investments (Details 9) Sheet http://principal.com/role/DisclosureInvestmentsDetails9 Investments (Details 9) false false R54.htm 4049 - Disclosure - Investments (Details 10) Sheet http://principal.com/role/DisclosureInvestmentsDetails10 Investments (Details 10) false false R55.htm 4050 - Disclosure - Investments (Details 11) Sheet http://principal.com/role/DisclosureInvestmentsDetails11 Investments (Details 11) false false R56.htm 4051 - Disclosure - Investments (Details 12) Sheet http://principal.com/role/DisclosureInvestmentsDetails12 Investments (Details 12) false false R57.htm 4052 - Disclosure - Investments (Details 13) Sheet http://principal.com/role/DisclosureInvestmentsDetails13 Investments (Details 13) false false R58.htm 4053 - Disclosure - Investments (Details 14) Sheet http://principal.com/role/DisclosureInvestmentsDetails14 Investments (Details 14) false false R59.htm 4054 - Disclosure - Investments (Details 15) Sheet http://principal.com/role/DisclosureInvestmentsDetails15 Investments (Details 15) false false R60.htm 4055 - Disclosure - Investments (Details 16) Sheet http://principal.com/role/DisclosureInvestmentsDetails16 Investments (Details 16) false false R61.htm 4056 - Disclosure - Derivative Financial Instruments (Details) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails Derivative Financial Instruments (Details) false false R62.htm 4057 - Disclosure - Derivative Financial Instruments (Details 2) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails2 Derivative Financial Instruments (Details 2) false false R63.htm 4058 - Disclosure - Derivative Financial Instruments (Details 3) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails3 Derivative Financial Instruments (Details 3) false false R64.htm 4059 - Disclosure - Derivative Financial Instruments (Details 4) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails4 Derivative Financial Instruments (Details 4) false false R65.htm 4060 - Disclosure - Derivative Financial Instruments (Details 5) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails5 Derivative Financial Instruments (Details 5) false false R66.htm 4061 - Disclosure - Derivative Financial Instruments (Details 6) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails6 Derivative Financial Instruments (Details 6) false false R67.htm 4062 - Disclosure - Derivative Financial Instruments (Details 7) Sheet http://principal.com/role/DisclosureDerivativeFinancialInstrumentsDetails7 Derivative Financial Instruments (Details 7) false false R68.htm 4063 - Disclosure - Income Taxes (Details) Sheet http://principal.com/role/DisclosureIncomeTaxesDetails Income Taxes (Details) false false R69.htm 4070 - Disclosure - Employee and Agent Benefits (Details) Sheet http://principal.com/role/DisclosureEmployeeAndAgentBenefitsDetails Employee and Agent Benefits (Details) false false R70.htm 4080 - Disclosure - Contingencies, Guarantees and Indemnifications (Details) Sheet http://principal.com/role/DisclosureContingenciesGuaranteesAndIndemnificationsDetails Contingencies, Guarantees and Indemnifications (Details) false false R71.htm 4090 - Disclosure - Stockholders' Equity (Details) Sheet http://principal.com/role/DisclosureStockholdersEquityDetails Stockholders' Equity (Details) false false R72.htm 4091 - Disclosure - Stockholders' Equity (Details 2) Sheet http://principal.com/role/DisclosureStockholdersEquityDetails2 Stockholders' Equity (Details 2) false false R73.htm 4092 - Disclosure - Stockholders' Equity (Details 3) Sheet http://principal.com/role/DisclosureStockholdersEquityDetails3 Stockholders' Equity (Details 3) false false R74.htm 4100 - Disclosure - Fair Value Measurements (Details) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails Fair Value Measurements (Details) false false R75.htm 4101 - Disclosure - Fair Value Measurements (Details 2) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails2 Fair Value Measurements (Details 2) false false R76.htm 4102 - Disclosure - Fair Value Measurements (Details 3) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails3 Fair Value Measurements (Details 3) false false R77.htm 4103 - Disclosure - Fair Value Measurements (Details 4) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails4 Fair Value Measurements (Details 4) false false R78.htm 4104 - Disclosure - Fair Value Measurements (Details 5) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails5 Fair Value Measurements (Details 5) false false R79.htm 4105 - Disclosure - Fair Value Measurements (Details 6) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails6 Fair Value Measurements (Details 6) false false R80.htm 4106 - Disclosure - Fair Value Measurements (Details 7) Sheet http://principal.com/role/DisclosureFairValueMeasurementsDetails7 Fair Value Measurements (Details 7) false false R81.htm 4110 - Disclosure - Segment Information (Details) Sheet http://principal.com/role/DisclosureSegmentInformationDetails Segment Information (Details) false false R82.htm 4111 - Disclosure - Segment Information (Details 2) Sheet http://principal.com/role/DisclosureSegmentInformationDetails2 Segment Information (Details 2) false false R83.htm 4112 - Disclosure - Segment Information (Details 3) Sheet http://principal.com/role/DisclosureSegmentInformationDetails3 Segment Information (Details 3) false false R84.htm 4113 - Disclosure - Segment Information (Details 4) Sheet http://principal.com/role/DisclosureSegmentInformationDetails4 Segment Information (Details 4) false false R85.htm 4120 - Disclosure - Stock-Based Compensation Plans (Details) Sheet http://principal.com/role/DisclosureStockBasedCompensationPlansDetails Stock-Based Compensation Plans (Details) false false R86.htm 4121 - Disclosure - Stock-Based Compensation Plans (Details 2) Sheet http://principal.com/role/DisclosureStockBasedCompensationPlansDetails2 Stock-Based Compensation Plans (Details 2) false false R87.htm 4122 - Disclosure - Stock-Based Compensation Plans (Details 3) Sheet http://principal.com/role/DisclosureStockBasedCompensationPlansDetails3 Stock-Based Compensation Plans (Details 3) false false R88.htm 4130 - Disclosure - Earnings Per Common Share (Details) Sheet http://principal.com/role/DisclosureEarningsPerCommonShareDetails Earnings Per Common Share (Details) false false R89.htm 4140 - Disclosure - Condensed Consolidating Financial Information (Details) Sheet http://principal.com/role/DisclosureFinancialInformationDetails Condensed Consolidating Financial Information (Details) false false R90.htm 4141 - Disclosure - Condensed Consolidating Financial Information (Details 2) Sheet http://principal.com/role/DisclosureFinancialInformationDetails2 Condensed Consolidating Financial Information (Details 2) false false R91.htm 4142 - Disclosure - Condensed Consolidating Financial Information (Details 3) Sheet http://principal.com/role/DisclosureFinancialInformationDetails3 Condensed Consolidating Financial Information (Details 3) false false R92.htm 4143 - Disclosure - Condensed Consolidating Financial Information (Details 4) Sheet http://principal.com/role/DisclosureFinancialInformationDetails4 Condensed Consolidating Financial Information (Details 4) false false R93.htm 4144 - Disclosure - Condensed Consolidating Financial Information (Details 5) Sheet http://principal.com/role/DisclosureFinancialInformationDetails5 Condensed Consolidating Financial Information (Details 5) false false R94.htm 4145 - Disclosure - Condensed Consolidating Financial Information (Details 6) Sheet http://principal.com/role/DisclosureFinancialInformationDetails6 Condensed Consolidating Financial Information (Details 6) false false All Reports Book All Reports Element pfg_FairValueInputsCreditSpreadRate had a mix of decimals attribute values: 3 4. Element us-gaap_FairValueInputsLossSeverity had a mix of decimals attribute values: 2 3. Element us-gaap_FairValueInputsProbabilityOfDefault had a mix of decimals attribute values: 2 3. 'Monetary' elements on report '4020 - Disclosure - Acquisition (Details)' had a mix of different decimal attribute values. 'Monetary' elements on report '4031 - Disclosure - Variable Interest Entities (Details 2)' had a mix of different decimal attribute values. 'Monetary' elements on report '4042 - Disclosure - Investments (Details 3)' had a mix of different decimal attribute values. Process Flow-Through: 0010 - Statement - Consolidated Statements of Financial Position Process Flow-Through: 0015 - Statement - Consolidated Statements of Financial Position (Parenthetical) Process Flow-Through: 0020 - Statement - Consolidated Statements of Operations Process Flow-Through: 0030 - Statement - Consolidated Statements of Comprehensive Income Process Flow-Through: 0045 - Statement - Consolidated Statements of Stockholders' Equity (Parenthetical) Process Flow-Through: 0050 - Statement - Consolidated Statements of Cash Flows pfg-20130331.xml pfg-20130331.xsd pfg-20130331_cal.xml pfg-20130331_def.xml pfg-20130331_lab.xml pfg-20130331_pre.xml true true