XML 37 R67.htm IDEA: XBRL DOCUMENT v2.4.1.9

Fair Value of Assets and Liabilities Fair Value of Assets and Liabilities (Changes in Level 3 Assets and Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014		Dec. 31, 2014	Dec. 31, 2013
Funds Withheld At Interest Embedded Derivatives [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	$ 22,094us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		$ (176,270)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	19,769us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		(99,029)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		77,241us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(2,325)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		77,241us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(2,325)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Funds Withheld At Interest Embedded Derivatives [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Nonredeemable Preferred Stock [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	7,904us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		4,962us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	88us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	29us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(29)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		4,962us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	7,992us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Nonredeemable Preferred Stock [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_NonredeemablePreferredStockMember
Longevity Swap [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	7,727us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	1,821us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	8,602us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Longevity Swap [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(946)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(946)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_LongevitySwapMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	(1,132,270)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(911,987)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(1,085,166)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	(868,726)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss)	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	(11,644)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]	(15,193)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]	19,433us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3	18,999us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(28,245)us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(24,211)us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	(25,133)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(23,661)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(48,324)us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(43,273)us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		(23,840)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	(29,326)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Interest Sensitive Contract Liabilities Embedded Derivatives [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Mortality Swap [Member]
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value	(1,276)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember				(797)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss)	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3 / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Mortality Swap [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Liabilities Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(479)us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings	(479)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = rga_MortalitySwapMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,310,427us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		1,345,289us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	6,069us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		2,450us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	36,900us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]	79,512us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]	(38,747)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(59,600)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]	(51,944)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		6,930us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(5,609)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		(50,517)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	1,286,979us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		1,291,701us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(803)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		(1,062)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(803)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		(1,111)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(405)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		(161)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Corporate Debt Securities [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CorporateDebtSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	188,094us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		153,505us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	523us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		2,887us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	11,439us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]	18,750us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(714)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]	(744)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(5,719)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]	(6,172)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	600us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		10,563us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(1,422)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		(1,024)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	192,579us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		177,927us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(141)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		52us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(140)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		56us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(82)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		106us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Residential mortgage-backed securities | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ResidentialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	572,960us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		471,848us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	3,632us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		5,501us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	40,991us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]	59,224us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(7,356)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]	(6,612)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(4,122)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]	(6,315)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	9,055us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		5,948us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(7,216)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		(29,280)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	609,436us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		502,675us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	1,399us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		2,050us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	1,419us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		2,057us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	73us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		304us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Asset-backed securities | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_AssetBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	86,746us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		101,785us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	(310)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		3,035us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	(956)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]	(14,626)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(5,120)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]	(279)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	12,828us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	93,869us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		90,373us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	589us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		428us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	594us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		372us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	87us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		86us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | Commercial Mortgage Backed Securities [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_CommercialMortgageBackedSecuritiesMember
Available-for-sale Securities [Member] | US Treasury And Government Member
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	28,529us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	176us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	121us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(944)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	27,756us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	(19)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(19)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(107)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	42,711us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		43,776us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	25us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		113us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(29)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]	(64)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(835)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	41,875us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		43,833us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	7us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		12us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	7us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		12us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	(4)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		(4)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | US States and Political Subdivisions Debt Securities [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USStatesAndPoliticalSubdivisionsMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	19,663us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		37,997us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)	182us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements	(310)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]	(298)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	(4,333)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		(26,542)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value	15,202us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		11,157us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember		0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | Foreign Government Debt Securities [Member] | Other Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)	0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings	0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / us-gaap_EligibleItemOrGroupForFairValueOptionAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_OtherIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_ForeignGovernmentDebtSecuritiesMember
Available-for-sale Securities [Member] | US Treasury And Government Member
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value			40,919us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss)			305us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases			128us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales			0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements			(3,029)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember	[1]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3			0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3			0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value			38,031us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Investment Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			(97)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings			(97)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InvestmentIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Investment Related Gains Losses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings			(195)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_InvestmentRelatedGainsLossesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Insurance Claims [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings			0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InsuranceClaimsMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Interest Income [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings			0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = us-gaap_InterestIncomeMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Available-for-sale Securities [Member] | US Treasury And Government Member | Policy Acquisition Costs And Other Insurance Expenses [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss)			0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings			$ 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 / rga_FairValueByMajorCategoryAxis = us-gaap_AvailableforsaleSecuritiesMember / us-gaap_IncomeStatementLocationAxis = rga_PolicyAcquisitionCostsAndOtherInsuranceExpensesMember / us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis = us-gaap_USTreasuryAndGovernmentMember
[1] The amount reported within purchases, sales and settlements is the purchase price (for purchases) and the sales/settlement proceeds (for sales and settlements) based upon the actual date purchased or sold/settled. Items purchased and sold/settled in the same period are excluded from the rollforward. The Company had no issuances during the period.

X

- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those assets still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_FairValueAssetsMeasuredOnRecurringBasisUnobservableInputReconciliationLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of unrealized (holding) gain (loss) which is included in the statement of income (or changes in net assets) related to those liabilities still held at the reporting date for which fair value is measured on a recurring basis using significant unobservable inputs (Level 3).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	us-gaap_FairValueLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationCalculationRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of transfers of financial instrument classified as a liability into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of transfers of financial instrument classified as a liability out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersOutOfLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of settlement of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Amount of gain (loss) recognized on the income statement for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of purchases of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPurchases
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Amount of sales of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySales
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of settlements of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilitySettlements
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationsRecurringBasisLiabilityValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Details

Name:	rga_FairValueByMajorCategoryAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_EligibleItemOrGroupForFairValueOptionAxis=us-gaap_AvailableforsaleSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=rga_FundsWithheldAtInterestEmbeddedDerivativesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=rga_InterestSensitiveContractLiabilitiesEmbeddedDerivativesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=rga_LongevitySwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=rga_MortalitySwapMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_NonredeemablePreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: