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FAIR VALUE MEASUREMENTS - Changes in Available-For-Sale Investments and Derivatives Classified as Level 3 (Detail) (USD $)
In Millions, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period $ 346us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue $ 3,197us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Realized gains or losses included in earnings (189)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1 105us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
Unrealized gains or losses included in other comprehensive income (140)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss (105)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
Sales (60)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales (387)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
Settlements 83us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements (13)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
Transfers into Level 3 149us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 [1] 174us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3 [2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 (2,625)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3 [3]
Balance, end of period 189us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue 346us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Change in unrealized gain (losses) still held (189)us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss 105us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
Fixed Maturities | Mortgage- and asset-backed securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 369us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
338us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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= us-gaap_AssetBackedSecuritiesMember
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= us-gaap_FixedMaturitiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Unrealized gains or losses included in other comprehensive income (134)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(72)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Settlements (12)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(13)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[1] 125us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(9)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[3]
Balance, end of period 223us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
369us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_AssetBackedSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Fixed Maturities | Public utilities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
420us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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= us-gaap_PublicUtilityBondsMember
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= us-gaap_FixedMaturitiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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= us-gaap_PublicUtilityBondsMember
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= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Unrealized gains or losses included in other comprehensive income 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(20)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
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= us-gaap_FixedMaturitiesMember
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
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= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
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= us-gaap_FixedMaturitiesMember
Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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= us-gaap_FixedMaturitiesMember
(400)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[1] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[3]
Balance, end of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
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= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_PublicUtilityBondsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Fixed Maturities | Sovereign and supranational    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
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= us-gaap_FixedMaturitiesMember
418us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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= us-gaap_FixedMaturitiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
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= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
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= us-gaap_FixedMaturitiesMember
Unrealized gains or losses included in other comprehensive income 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
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Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
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Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
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Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
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[1] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
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= us-gaap_FixedMaturitiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
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(418)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_SovereignDebtMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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[3]
Balance, end of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
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0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
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Fixed Maturities | Banks/financial Institutions    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 23us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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1,024us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
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Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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Unrealized gains or losses included in other comprehensive income 3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
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(4)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
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Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
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Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
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Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[1] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(997)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[3]
Balance, end of period 26us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
23us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Fixed Maturities | Other corporate    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
986us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
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/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Unrealized gains or losses included in other comprehensive income 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[1] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
(986)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
[3]
Balance, end of period 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= us-gaap_CorporateDebtSecuritiesMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_FixedMaturitiesMember
Perpetual securities | Banks/financial Institutions    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 52us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
215us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Unrealized gains or losses included in other comprehensive income 8us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Sales (60)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Transfers into Level 3 149us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
[1] 49us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
(215)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
[3]
Balance, end of period 149us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
52us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_InvestmentTypeAxis
= afl_BanksAndFinancialInstitutionsMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= afl_PerpetualSecuritiesMember
Equity securities    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
4us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Realized gains or losses included in earnings 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Unrealized gains or losses included in other comprehensive income 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
(1)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Transfers into Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
[1] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersIntoLevel3
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
[2]
Transfers out of Level 3 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
[3]
Balance, end of period 3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
3us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Change in unrealized gain (losses) still held 0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
0us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_EquitySecuritiesMember
Derivatives | Interest rate swaps    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
Balance, beginning of period 1us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] 29us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Realized gains or losses included in earnings (1)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] (8)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Unrealized gains or losses included in other comprehensive income 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInOtherComprehensiveIncomeLoss
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Purchases 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Issuances 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Sales 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] (20)us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4]
Settlements 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= us-gaap_DerivativeMember
[4] 0us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements
/ us-gaap_DerivativeInstrumentRiskAxis
= us-gaap_InterestRateSwapMember
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
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[4]
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[2],[4]
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[3],[4]
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[4]
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[4]
Derivatives | Foreign currency swaps    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
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[4]
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[4] 84us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetGainLossIncludedInEarnings1
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[4]
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[4]
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[4]
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[4]
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[4]
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[2],[4]
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[3],[4]
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[4]
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[4]
Derivatives | Credit default swaps    
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]    
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[4]
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[4]
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[4]
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[3],[4]
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[4]
Change in unrealized gain (losses) still held $ 3us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
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[4] $ 29us-gaap_FairValueAssetsMeasuredOnRecurringBasisChangeInUnrealizedGainLoss
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[4]
[1] Due to use of estimated redemption price
[2] Due to a lack of visibility to observe significant inputs to price
[3] A result of changing our pricing methodology to a valuation method that uses observable market data as significant inputs to estimate fair value
[4] Derivative assets and liabilities are presented net