Fair Value of Financial Instruments - Changes to Fair Value of Financial Instruments Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2018
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	$ 4,400	$ 2,920	$ 3,267	$ 138
F&G Acquisition				2,754
Assets, Total Gains (Losses) Included in Earnings	(2)	1	12	(63)
Assets, Total Gains (Losses) Included in AOCI	11	46	(19)	68
Assets, Purchases	1,417	128	2,959	220
Assets, Sales	(111)	(1)	(119)	(1)
Assets, Settlements	(568)	(154)	(913)	(177)
Assets, Net transfer In (Out) of Level 3	(44)	(90)	(84)	(89)
Balance at End of Period	5,103	2,850	5,103	2,850
Change in Unrealized Gains (Losses) Incl in OCI	11	48	93	73
Liabilities
Balance at Beginning of Period	3,759	2,957	3,409	0
F&G Acquisition				2,857
Liabilities, Total Gains (Losses) Included in Earnings	(320)	209	35	309
Liabilities, Total Gains (Losses) Included in AOCI	0	0	0	0
Liabilities, Purchases	0	0	0	0
Liabilities, Sales	0	0	(4)	0
Liabilities, Settlements	0	0	(1)	0
Liabilities, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	3,439	3,166	3,439	3,166
Change in Unrealized Gains (Losses) Incl in OCI	0	0	0	0
Future policy benefits
Liabilities
Balance at Beginning of Period		5	5	0
F&G Acquisition				5
Liabilities, Total Gains (Losses) Included in Earnings		0	0	0
Liabilities, Total Gains (Losses) Included in AOCI		0	0	0
Liabilities, Purchases		0	0	0
Liabilities, Sales		0	(4)	0
Liabilities, Settlements		0	(1)	0
Liabilities, Net transfer In (Out) of Level 3		0	0	0
Balance at End of Period	0	5	0	5
Change in Unrealized Gains (Losses) Incl in OCI		0	0	0
FIA embedded derivatives, included in contractholder funds
Liabilities
Balance at Beginning of Period	3,759	2,952	3,404	0
F&G Acquisition				2,852
Liabilities, Total Gains (Losses) Included in Earnings	(320)	209	35	309
Liabilities, Total Gains (Losses) Included in AOCI	0	0	0	0
Liabilities, Purchases	0	0	0	0
Liabilities, Sales	0	0	0	0
Liabilities, Settlements	0	0	0	0
Liabilities, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	3,439	3,161	3,439	3,161
Change in Unrealized Gains (Losses) Incl in OCI		0	0	0
Asset-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	2,309	1,016	1,350	0
F&G Acquisition				854
Assets, Total Gains (Losses) Included in Earnings	(1)	(1)	(1)	(1)
Assets, Total Gains (Losses) Included in AOCI	14	11	11	20
Assets, Purchases	1,188	118	2,359	209
Assets, Sales	(97)	(1)	(97)	(1)
Assets, Settlements	(125)	(109)	(307)	(114)
Assets, Net transfer In (Out) of Level 3	(44)	(90)	(71)	(23)
Balance at End of Period	3,244	944	3,244	944
Change in Unrealized Gains (Losses) Incl in OCI	11	12	25	21
Commercial mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	25	26	26	0
F&G Acquisition				26
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	(1)	0	(2)	0
Assets, Purchases	12	0	12	0
Assets, Sales	0	0	0	0
Assets, Settlements	0	0	0	0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	36	26	36	26
Change in Unrealized Gains (Losses) Incl in OCI	0	1	1	1
Corporates
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	1,201	1,264	1,289	17
F&G Acquisition				1,238
Assets, Total Gains (Losses) Included in Earnings	(1)	(1)	8	(4)
Assets, Total Gains (Losses) Included in AOCI	(3)	21	(29)	47
Assets, Purchases	19	3	76	3
Assets, Sales	(14)	0	(22)	0
Assets, Settlements	(89)	(20)	(196)	(34)
Assets, Net transfer In (Out) of Level 3	0	0	(13)	0
Balance at End of Period	1,113	1,267	1,113	1,267
Change in Unrealized Gains (Losses) Incl in OCI	(2)	19	35	45
Hybrids
Fixed maturity securities available-for-sale:
Balance at Beginning of Period		4	4	0
F&G Acquisition				4
Assets, Total Gains (Losses) Included in Earnings		0	0	0
Assets, Total Gains (Losses) Included in AOCI		0	0	0
Assets, Purchases		0	0	0
Assets, Sales		0	0	0
Assets, Settlements		0	(4)	0
Assets, Net transfer In (Out) of Level 3		0	0	0
Balance at End of Period	0	4	0	4
Change in Unrealized Gains (Losses) Incl in OCI		0	0	0
Municipals
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	43	40	43	0
F&G Acquisition				38
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	0	2	0	4
Assets, Purchases	0	0	0	0
Assets, Sales	0	0	0	0
Assets, Settlements	0	0	0	0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	43	42	43	42
Change in Unrealized Gains (Losses) Incl in OCI	0	2	7	5
Residential mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	443	509	483	0
F&G Acquisition				534
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	(3)	12	(1)	(3)
Assets, Purchases	4	5	14	6
Assets, Sales	0	0	0	0
Assets, Settlements	(50)	(25)	(102)	(29)
Assets, Net transfer In (Out) of Level 3	0	0	0	(7)
Balance at End of Period	394	501	394	501
Change in Unrealized Gains (Losses) Incl in OCI	1	14	22	1
Foreign Governments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	17	16	17	0
F&G Acquisition				16
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	1	0	1	0
Assets, Purchases	0	0	0	0
Assets, Sales	0	0	0	0
Assets, Settlements	0	0	0	0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	18	16	18	16
Change in Unrealized Gains (Losses) Incl in OCI	0	0	2	0
Short-Term
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	303		0
Assets, Total Gains (Losses) Included in Earnings	0		0
Assets, Total Gains (Losses) Included in AOCI	1		2
Assets, Purchases	192		494
Assets, Sales	0		0
Assets, Settlements	(304)		(304)
Assets, Net transfer In (Out) of Level 3	0		0
Balance at End of Period	192		192
Change in Unrealized Gains (Losses) Incl in OCI	1		1
Equity securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	10	1	5	1
F&G Acquisition				1
Assets, Total Gains (Losses) Included in Earnings	(1)	1	1	0
Assets, Total Gains (Losses) Included in AOCI	1	0	2	0
Assets, Purchases	2	2	4	2
Assets, Sales	0	0	0	0
Assets, Settlements	0	0	0	0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	12	4	12	4
Change in Unrealized Gains (Losses) Incl in OCI	0	0	0	0
Available-for-sale embedded derivative
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	30	21	27	0
F&G Acquisition				20
Assets, Total Gains (Losses) Included in Earnings	1	2	4	3
Assets, Total Gains (Losses) Included in AOCI	0	0	0	0
Assets, Purchases	0	0	0	0
Assets, Sales	0	0	0	0
Assets, Settlements	0	0	0	0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	31	23	31	23
Change in Unrealized Gains (Losses) Incl in OCI	0	0	0	0
Other long-term investments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period		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		0
Change in Unrealized Gains (Losses) Incl in OCI				0
Credit linked note
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	19	23	23	0
F&G Acquisition					$ 23
Assets, Total Gains (Losses) Included in Earnings	0	0	0		0
Assets, Total Gains (Losses) Included in AOCI	1	0	(3)		0
Assets, Purchases	0	0	0		0
Assets, Sales	0	0	0		0
Assets, Settlements	0	0	0		$ 0
Assets, Net transfer In (Out) of Level 3	0	0	0	0
Balance at End of Period	20	23	20	23
Change in Unrealized Gains (Losses) Incl in OCI	$ 0	$ 0	$ 0	$ 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, Liability, 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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