Fair Value of Financial Instruments - Changes to Fair Value of Financial Instruments Level 3 (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	$ 3,267	$ 138
F&G Acquisition		2,754
Assets, Total Gains (Losses) Included in Earnings	15	(57)
Assets, Total Gains (Losses) Included in AOCI	(48)	93
Assets, Purchases	4,449	756
Assets, Sales	(120)	(1)
Assets, Settlements	(1,449)	(282)
Assets, Net transfer In (Out) of Level 3	(514)	(134)
Balance at End of Period	5,600	3,267
Change in Unrealized Included in OCI	59	59
Liabilities, Fair Value Disclosure [Abstract]
Balance at Beginning of Period	3,409	0
F&G Acquisition		2,857
Liabilities, Total Gains (Losses) Included in Earnings	479	552
Liabilities, Total Gains (Losses) Included in AOCI	0	0
Liabilities, Purchases	0	0
Liabilities, Sales	(4)	0
Liabilities, Settlements	(1)	0
Liabilities, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	3,883	3,409
Change in Unrealized Included in OCI	0	0
Future policy benefits
Liabilities, Fair Value Disclosure [Abstract]
Balance at Beginning of Period	5	0
F&G Acquisition		5
Liabilities, Total Gains (Losses) Included in Earnings	0	0
Liabilities, Total Gains (Losses) Included in AOCI	0	0
Liabilities, Purchases	0	0
Liabilities, Sales	(4)	0
Liabilities, Settlements	(1)	0
Liabilities, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	0	5
Change in Unrealized Included in OCI	0	0
FIA embedded derivatives, included in contractholder funds
Liabilities, Fair Value Disclosure [Abstract]
Balance at Beginning of Period	3,404	0
F&G Acquisition		2,852
Liabilities, Total Gains (Losses) Included in Earnings	479	552
Liabilities, Total Gains (Losses) Included in AOCI	0	0
Liabilities, Purchases	0	0
Liabilities, Sales	0	0
Liabilities, Settlements	0	0
Liabilities, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	3,883	3,404
Change in Unrealized Included in OCI	0	0
Asset-backed securities
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	1,350	0
F&G Acquisition		854
Assets, Total Gains (Losses) Included in Earnings	(1)	(1)
Assets, Total Gains (Losses) Included in AOCI	(8)	21
Assets, Purchases	3,417	633
Assets, Sales	(97)	(1)
Assets, Settlements	(595)	(133)
Assets, Net transfer In (Out) of Level 3	(107)	(23)
Balance at End of Period	3,959	1,350
Change in Unrealized Included in OCI	4	10
Commercial mortgage-backed securities
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	26	0
F&G Acquisition		26
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	(3)	0
Assets, Purchases	12	0
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	35	26
Change in Unrealized Included in OCI	1	0
Corporates
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	1,289	17
F&G Acquisition		1,238
Assets, Total Gains (Losses) Included in Earnings	8	(3)
Assets, Total Gains (Losses) Included in AOCI	(40)	59
Assets, Purchases	161	110
Assets, Sales	(23)	0
Assets, Settlements	(247)	(87)
Assets, Net transfer In (Out) of Level 3	(13)	(45)
Balance at End of Period	1,135	1,289
Change in Unrealized Included in OCI	23	43
Hybrids
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	4	0
F&G Acquisition		4
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	(4)	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	0	4
Change in Unrealized Included in OCI	0	0
Municipals
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	43	0
F&G Acquisition		38
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	0	5
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	43	43
Change in Unrealized Included in OCI	7	5
Residential mortgage-backed securities
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	483	0
F&G Acquisition		534
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	(1)	7
Assets, Purchases	14	11
Assets, Sales	0	0
Assets, Settlements	(102)	(62)
Assets, Net transfer In (Out) of Level 3	(394)	(7)
Balance at End of Period	0	483
Change in Unrealized Included in OCI	22	0
Foreign Governments
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	17	0
F&G Acquisition		16
Assets, Total Gains (Losses) Included in Earnings	0	0
Assets, Total Gains (Losses) Included in AOCI	1	1
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	18	17
Change in Unrealized Included in OCI	2	1
Short-term Investments
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	0
Assets, Total Gains (Losses) Included in Earnings	0
Assets, Total Gains (Losses) Included in AOCI	2
Assets, Purchases	820
Assets, Sales	0
Assets, Settlements	(501)
Assets, Net transfer In (Out) of Level 3	0
Balance at End of Period	321	0
Change in Unrealized Included in OCI	0
Preferred securities
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	1	0
F&G Acquisition		1
Assets, Total Gains (Losses) Included in Earnings	(1)	0
Assets, Total Gains (Losses) Included in AOCI	1	0
Assets, Purchases	1	0
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	2	1
Change in Unrealized Included in OCI	0	0
Equity securities
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	4	1
F&G Acquisition		0
Assets, Total Gains (Losses) Included in Earnings	2	1
Assets, Total Gains (Losses) Included in AOCI	0	0
Assets, Purchases	3	2
Assets, Sales	0	0
Assets, Settlements	0	0
Assets, Net transfer In (Out) of Level 3	0	0
Balance at End of Period	9	4
Change in Unrealized Included in OCI	0	0
Available-for-sale embedded derivative
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	27	0
F&G Acquisition		20
Assets, Total Gains (Losses) Included in Earnings	7	7
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	34	27
Change in Unrealized Included in OCI	0	0
Credit linked note
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	23	0
F&G Acquisition		23
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	23	23
Change in Unrealized Included in OCI	0	0
Investment in affiliate
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	0
Assets, Total Gains (Losses) Included in Earnings	0
Assets, Total Gains (Losses) Included in AOCI	0
Assets, Purchases	21
Assets, Sales	0
Assets, Settlements	0
Assets, Net transfer In (Out) of Level 3	0
Balance at End of Period	21	0
Change in Unrealized Included in OCI	0
Other long-term investments
Debt Securities, Available-for-sale [Abstract]
Balance at Beginning of Period	$ 0	120
F&G Acquisition		0
Assets, Total Gains (Losses) Included in Earnings		(61)
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		(59)
Balance at End of Period		0
Change in Unrealized Included in OCI		$ 0

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Business Combinations

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Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Business Combinations

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

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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.

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

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