Fair Value of Financial Instruments - Changes to Fair Value of Financial Instruments Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2018
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	$ 3,467	$ 15	$ 3,267	$ 138
F&G Acquisition		2,754		2,754
Assets, Total Gains (Losses) Included in Earnings	4	0	14	(64)
Assets, Total Gains (Losses) Included in AOCI	30	22	(30)	22
Assets, Purchases	1,138	92	1,542	92
Assets, Sales	(8)	0	(8)	0
Assets, Settlements	(205)	(23)	(345)	(23)
Assets, Net transfer In (Out) of Level 3	(26)	60	(40)	1
Balance at End of Period	4,400	2,920	4,400	2,920
Change in Unrealized Gains (Losses) Incl in OCI	33	25	82	25
Liabilities
Balance at Beginning of Period	3,297	0	3,409	0
F&G Acquisition		2,857		2,857
Liabilities, Total Gains (Losses) Included in Earnings	466	100	355	100
Liabilities, Total Gains (Losses) Included in AOCI	0	0	0	0
Liabilities, Purchases	0	0	0	0
Liabilities, Sales	(4)	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	3,759	2,957	3,759	2,957
Change in Unrealized Gains (Losses) Incl in OCI	0	0	0	0
Future policy benefits
Liabilities
Balance at Beginning of Period	4	0		0
F&G Acquisition		5		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	4	0		0
Liabilities, Settlements	0	0		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	3,293	0	3,404	0
F&G Acquisition		2,852		2,852
Liabilities, Total Gains (Losses) Included in Earnings	466	100	355	100
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	3,759	2,952	3,759	2,952
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	1,593	0	1,350	0
F&G Acquisition		854		854
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	20	9	(3)	9
Assets, Purchases	813	91	1,171	91
Assets, Sales	0	0	0	0
Assets, Settlements	(90)	(5)	(182)	(5)
Assets, Net transfer In (Out) of Level 3	(27)	67	(27)	67
Balance at End of Period	2,309	1,016	2,309	1,016
Change in Unrealized Gains (Losses) Incl in OCI	18	9	14	9
Commercial mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	25	0	26	0
F&G Acquisition		26		26
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	0	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	25	26	25	26
Change in Unrealized Gains (Losses) Incl in OCI	0	0	1	0
Corporates
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	1,247	14	1,289	17
F&G Acquisition		1,238		1,238
Assets, Total Gains (Losses) Included in Earnings	2	0	9	(3)
Assets, Total Gains (Losses) Included in AOCI	16	26	(26)	26
Assets, Purchases	18	0	57	0
Assets, Sales	(7)	0	(8)	0
Assets, Settlements	(76)	(14)	(107)	(14)
Assets, Net transfer In (Out) of Level 3	1	0	(13)	0
Balance at End of Period	1,201	1,264	1,201	1,264
Change in Unrealized Gains (Losses) Incl in OCI	18	26	37	26
Hybrids
Fixed maturity securities available-for-sale:
Balance at Beginning of Period		0	4	0
F&G Acquisition		4		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	41	0	43	0
F&G Acquisition		38		38
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	2	2	0	2
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	40	43	40
Change in Unrealized Gains (Losses) Incl in OCI	3	3	7	3
Residential mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	487	0	483	0
F&G Acquisition		534		534
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
Assets, Total Gains (Losses) Included in AOCI	(10)	(15)	2	(15)
Assets, Purchases	5	1	10	1
Assets, Sales	0	0	0	0
Assets, Settlements	(39)	(4)	(52)	(4)
Assets, Net transfer In (Out) of Level 3	0	(7)	0	(7)
Balance at End of Period	443	509	443	509
Change in Unrealized Gains (Losses) Incl in OCI	(6)	(13)	21	(13)
Foreign Governments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	17	0	17	0
F&G Acquisition		16		16
Assets, Total Gains (Losses) Included in Earnings	0	0	0	0
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	17	16	17	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	0		0
Assets, Total Gains (Losses) Included in Earnings	0		0
Assets, Total Gains (Losses) Included in AOCI	1		1
Assets, Purchases	302		302
Assets, Sales	0		0
Assets, Settlements	0		0
Assets, Net transfer In (Out) of Level 3	0		0
Balance at End of Period	303		303
Change in Unrealized Gains (Losses) Incl in OCI	0		0
Equity securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	10	1	5	1
F&G Acquisition		1		1
Assets, Total Gains (Losses) Included in Earnings	0	(1)	2	(1)
Assets, Total Gains (Losses) Included in AOCI	1	0	1	0
Assets, Purchases	0	0	2	0
Assets, Sales	(1)	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	10	1	10	1
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	28	0	27	0
F&G Acquisition		20		20
Assets, Total Gains (Losses) Included in Earnings	2	1	3	1
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	30	21	30	21
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, 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	0
F&G Acquisition		23			$ 23
Assets, Total Gains (Losses) Included in Earnings	0	0	0		0
Assets, Total Gains (Losses) Included in AOCI	0	0	(4)		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	19	23	19	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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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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