Managed Investment Entities - Narrative (Details) $ in Millions	12 Months Ended
Dec. 31, 2019 USD ($) collateralizedloanobligation	Dec. 31, 2018 USD ($) collateralizedloanobligation	Dec. 31, 2017 USD ($) collateralizedloanobligation
Variable Interest Entity [Line Items]
Percentage of investment of most subordinate debt tranche, Minimum	15.00%
Percentage of investment of most subordinate debt tranche, Maximum	60.90%
Number of collateralized loan obligation entities \| collateralizedloanobligation	11
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities		$ 45	$ 103
Face amount of managed investment entities liabilities purchased by subsidiaries after issuance date		7	71
Amount paid by subsidiaries to purchase managed investment entities liabilities after issuance date		$ 7	$ 71
Number of collateralized loan obligation entities formed during the period \| collateralizedloanobligation		1	2
Number of collateralized loan obligation entities that were substantially liquidated during the period \| collateralizedloanobligation		1	2
Difference between aggregate unpaid principal balance and fair value of CLOs' fixed maturity investments	$ 146	$ 232
Difference between aggregate unpaid principal balance and fair value of CLOs' debt	129	241
Carrying amount of CLO loans in default	10
Aggregate unpaid principal balance of CLO loans in default	25	0
Available for sale (AFS) fixed maturities	46,505	41,997
Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	165	188	$ 215
New collateralized loan obligation entities
Variable Interest Entity [Line Items]
Face value of liabilities issued by managed investment entities on issuance date		463	865
Face amount of managed investment entities liabilities purchased by subsidiaries at issuance date		31	$ 48
Subordinated debt obligations \| Variable interest entity, primary beneficiary
Variable Interest Entity [Line Items]
Aggregate fair value of investment in collateralized loan obligations	102
Collateralized loan obligations
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	4,280	4,278
Collateralized loan obligations \| Managed by third parties
Variable Interest Entity [Line Items]
Available for sale (AFS) fixed maturities	4,280	$ 4,280
Maximum
Variable Interest Entity [Line Items]
Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities	$ 1

Aggregate unpaid principal balance of variable interest entity loans in default

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- Definition

Amount paid by subsidiaries to purchase managed investment entities liabilities after issuance date.

+ References

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Carrying amount of variable interest entity loans in default.

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Difference between aggregate unpaid principal balance and fair value of variable interest entity debt.

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Difference between aggregate unpaid principal balance and fair value of variable interest entity investments.

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Face amount of managed investment entities liabilities purchased by subsidiaries after issuance date.

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Face amount of managed investment entities liabilities purchased by subsidiaries at issuance date.

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Face value of liabilities issued by managed investment entities.

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- Definition

Number of collateralized loan obligation entities.

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Number of collateralized loan obligation entities formed during the period.

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Number of collateralized loan obligation entities that were substantially liquidated during the period.

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- Definition

Maximum percentage of investment of most subordinate debt tranche of variable interest entity.

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Minimum percentage of investment of most subordinate debt tranche of variable interest entity.

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Proceeds received by subsidiaries related to sales and redemptions of managed investment entities liabilities.

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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- Definition

The reporting entity's maximum amount of exposure to loss as a result of its involvement with the Variable Interest Entity (VIE).

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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