Fair Value of Financial Instruments - Changes to Fair Value of Financial Instruments Level 3 (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2024	Mar. 31, 2023
Liabilities
Liabilities, Total Gains (Losses) Included in Earnings	$ 228	$ 385
Liabilities, Total Gains (Losses) Included in AOCI	0	0
Liabilities, Purchases	336	96
Liabilities, Sales	0	0
Liabilities, Settlements	(67)	(27)
Liabilities, Net transfer In (Out) of Level 3	$ 0	$ 0
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Recognized gains and losses, net	Recognized gains and losses, net
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Asset, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]	Unrealized (loss) gain on investments and other financial instruments, net of adjustments to intangible assets and unearned revenue (excluding investments in unconsolidated affiliates)	Unrealized (loss) gain on investments and other financial instruments, net of adjustments to intangible assets and unearned revenue (excluding investments in unconsolidated affiliates)
Level 3
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	$ 9,677	$ 8,286
Balance at End of Period	10,476	8,229
Liabilities
Balance at Beginning of Period	4,661	3,397
Balance at End of Period	5,180	3,893
Indexed annuities/IUL embedded derivatives, included in contractholder funds
Liabilities
Balance at Beginning of Period	4,258	3,115
Liabilities, Total Gains (Losses) Included in Earnings	200	385
Liabilities, Total Gains (Losses) Included in AOCI	0	0
Liabilities, Purchases	288	96
Liabilities, Sales	0	0
Liabilities, Settlements	(67)	(27)
Liabilities, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	4,679	3,569
Change in Unrealized Gains (Losses) Included in OCI	0	0
Interest Rate Swaps
Liabilities
Balance at Beginning of Period	0
Liabilities, Total Gains (Losses) Included in Earnings	19
Liabilities, Total Gains (Losses) Included in AOCI	0
Liabilities, Purchases	0
Liabilities, Sales	0
Liabilities, Settlements	0
Liabilities, Net transfer In (Out) of Level 3	0
Balance at End of Period	19
Change in Unrealized Gains (Losses) Included in OCI	0
Contingent consideration
Liabilities
Balance at Beginning of Period	0
Liabilities, Total Gains (Losses) Included in Earnings	9
Liabilities, Total Gains (Losses) Included in AOCI	0
Liabilities, Purchases	48
Liabilities, Sales	0
Liabilities, Settlements	0
Liabilities, Net transfer In (Out) of Level 3	0
Balance at End of Period	57
Change in Unrealized Gains (Losses) Included in OCI	0
Asset-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	7,122	6,263
Assets, Total Gains (Losses) Included in Earnings	(12)	(8)
Assets, Total Gains (Losses) Included in AOCI	104	18
Assets, Purchases	762	416
Assets, Sales	(19)	(83)
Assets, Settlements	(202)	(235)
Assets, Net transfer In (Out) of Level 3	(19)	(71)
Balance at End of Period	7,736	6,300
Change in Unrealized Included in OCI	104	18
Commercial mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	18	37
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	1
Assets, Purchases	1	12
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	(7)	(21)
Balance at End of Period	12	29
Change in Unrealized Included in OCI	0	1
Corporates
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	1,979	1,440
Assets, Total Gains (Losses) Included in Earnings	0	(1)
Assets, Total Gains (Losses) Included in AOCI	13	(23)
Assets, Purchases	217	133
Assets, Sales	(3)	0
Assets, Settlements	(22)	(5)
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	2,184	1,544
Change in Unrealized Included in OCI	13	(23)
Municipals
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	49	29
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	1	3
Assets, Purchases	0	0
Assets, Sales	(32)	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	18	32
Change in Unrealized Included in OCI	1	3
Residential mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	3	302
Assets, Total Gains (Losses) Included in Earnings	0	1
Assets, Total Gains (Losses) Included in AOCI	0	8
Assets, Purchases	1	8
Assets, Sales	0	0
Assets, Settlements	0	(8)
Assets, Net transfer In (Out) of Level 3	0	(299)
Balance at End of Period	4	12
Change in Unrealized Included in OCI	0	8
Foreign Governments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	16	16
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	0	0
Assets, Sales	0	0
Assets, Settlements	(11)	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	5	16
Change in Unrealized Included in OCI	0	0
Preferred securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	8	1
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	0	0
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	8	1
Change in Unrealized Included in OCI	0	0
Equity securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	15	10
Assets, Total Gains (Losses) Included in Earnings	(1)	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	0	1
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	14	11
Change in Unrealized Included in OCI	0	0
Interest Rate Swaps
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	57
Assets, Total Gains (Losses) Included in Earnings	(48)
Assets, Total Gains (Losses) Included in AOCI	0
Assets, Purchases	0
Assets, Sales	0
Assets, Settlements	0
Assets, Net transfer In (Out) of Level 3	0
Balance at End of Period	9
Change in Unrealized Included in OCI	0
Investment in unconsolidated affiliates
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	285	23
Assets, Total Gains (Losses) Included in Earnings	58	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	0	84
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	343	107
Change in Unrealized Included in OCI	0	0
Short term investments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0	0
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	9	23
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	9	23
Change in Unrealized Included in OCI	0	0
Available-for-sale embedded derivative
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	27	23
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	3	2
Assets, Purchases	0	0
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	30	25
Change in Unrealized Included in OCI	3	2
Credit linked note
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	10	15
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	0	0
Assets, Sales	0	0
Assets, Settlements	(1)	(2)
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	9	13
Change in Unrealized Included in OCI	0	0
Secured borrowing receivable
Fixed maturity securities available-for-sale:
Balance at Beginning of Period		10
Assets, Total Gains (Losses) Included in Earnings		0
Assets, Total Gains (Losses) Included in AOCI		0
Assets, Purchases		0
Assets, Sales		0
Assets, Settlements		0
Assets, Net transfer In (Out) of Level 3		0
Balance at End of Period		10
Change in Unrealized Included in OCI		0
Subtotal Level 3 assets at fair value \| Level 3
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	9,589	8,169
Assets, Total Gains (Losses) Included in Earnings	(3)	(8)
Assets, Total Gains (Losses) Included in AOCI	121	9
Assets, Purchases	990	677
Assets, Sales	(54)	(83)
Assets, Settlements	(236)	(250)
Assets, Net transfer In (Out) of Level 3	(26)	(391)
Balance at End of Period	10,381	8,123
Change in Unrealized Included in OCI	121	9
Market risk benefits asset
Fixed maturity securities available-for-sale:
Balance at End of Period	95
Market risk benefits asset \| Level 3
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	88	117
Balance at End of Period		106
Subtotal Level 3 liabilities at fair value
Liabilities
Change in Unrealized Gains (Losses) Included in OCI	0	0
Subtotal Level 3 liabilities at fair value \| Level 3
Liabilities
Balance at Beginning of Period	4,258	3,115
Balance at End of Period	4,755	3,569
Market risk benefits liability \| Level 3
Liabilities
Balance at Beginning of Period	403	282
Balance at End of Period	$ 425	$ 324

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