Fair Value (Unobservable Input Reconciliation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Net Derivatives (2)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	$ 2	$ 16
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	1	9	$ (12)
Total realized/unrealized gains (losses) included in AOCI	12	(9)	(1)
Purchases (7)	20	0
Sales (7)	0	(14)
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	1	0
Balance, end of period	36	2	16
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	(11)	(4)	(10)
Changes in unrealized gains (losses) included in OCI	12	(9)
Net Embedded Derivatives (3)
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of period	(6,874)	(4,031)
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	(1,341)	(2,221)	(1,192)
Total realized/unrealized gains (losses) included in AOCI	0	0	0
Purchases (7)	0	0
Sales (7)	0	0
Issuances (7)	0	0
Settlements (7)	(95)	(622)
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	0	0
Balance, end of period	(8,310)	(6,874)	(4,031)
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	(874)	(2,297)	(1,450)
Changes in unrealized gains (losses) included in OCI	0	0
Corporate (1)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	688	461
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	(1)	(6)	0
Total realized/unrealized gains (losses) included in AOCI	(7)	(3)	15
Purchases (7)	951	409
Sales (7)	(53)	(117)
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	52	186
Transfers out of Level 3 (8)	(231)	(242)
Balance, end of period	1,399	688	461
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	(2)	(5)	0
Changes in unrealized gains (losses) included in OCI	(6)	(3)
Structured Securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	67	117
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	1
Total realized/unrealized gains (losses) included in AOCI	0	1	2
Purchases (7)	202	58
Sales (7)	(12)	(5)
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	11
Transfers out of Level 3 (8)	(37)	(115)
Balance, end of period	220	67	117
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	0
Changes in unrealized gains (losses) included in OCI	0	1
State and Political Subdivision
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0	73
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	1
Total realized/unrealized gains (losses) included in AOCI	0	0	(1)
Purchases (7)	0	0
Sales (7)	0	0
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	0	(73)
Balance, end of period	0	0	73
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	1
Changes in unrealized gains (losses) included in OCI	0	0
Foreign Government
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0	0
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	0
Total realized/unrealized gains (losses) included in AOCI	0	0	0
Purchases (7)	26	0
Sales (7)	0	0
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	0	0
Balance, end of period	26	0	0
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	0
Changes in unrealized gains (losses) included in OCI	0	0
Equity securities
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	3	8
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	0
Total realized/unrealized gains (losses) included in AOCI	0	0	0
Purchases (7)	10	0
Sales (7)	0	0
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	0	(5)
Balance, end of period	13	3	8
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	0
Changes in unrealized gains (losses) included in OCI	0	0
Short-term Investments
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	0	5
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	0
Total realized/unrealized gains (losses) included in AOCI	0	0	0
Purchases (7)	2	0
Sales (7)	0	(5)
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	0	0
Balance, end of period	2	0	5
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	0
Changes in unrealized gains (losses) included in OCI	0	0
Separate Account Assets (4)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	3	3
Total realized/unrealized gains (losses) included in net income (loss) (5) (6)	0	0	0
Total realized/unrealized gains (losses) included in AOCI	0	0	0
Purchases (7)	0	0
Sales (7)	0	0
Issuances (7)	0	0
Settlements (7)	0	0
Transfers into Level 3 (8)	0	0
Transfers out of Level 3 (8)	(3)	0
Balance, end of period	0	3	3
Changes in unrealized gains (losses) included in net income (loss) for the instruments still held at end of period	0	0	$ 0
Changes in unrealized gains (losses) included in OCI	$ 0	$ 0

Amount of unrealized gain (loss) recognized in other comprehensive income (OCI) from asset (liability) measured at fair value on recurring basis using unobservable input (level 3) and still held.

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

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

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Amount of unrealized gain (loss) recognized in income for derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held.

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Amount of gain (loss) recognized in income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

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Amount of gain (loss) recognized in other comprehensive income from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value on recurring basis using unobservable input (level 3).

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Amount of issuances of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of unrealized gain (loss) recognized in other comprehensive income (OCI) from derivative asset (liability) after deduction of derivative liability (asset), measured at fair value using unobservable input (level 3) and still held.

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