Fair Value of Financial Instruments - Changes to Fair Value of Financial Instruments Level 3 (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	$ 15	$ 125	$ 138
F&G Acquisition	2,754		2,754
Assets, Total Gains (Losses) Included in Earnings	0	5	(64)	$ 12
Assets, Total Gains (Losses) Included in AOCI	22	0	22	(1)
Assets, Purchases	92	0	92	5
Assets, Sales	0	0	0	(1)
Assets, Settlements	(23)	0	(23)	0
Assets, Net transfer In (Out) of Level 3	60	(2)	1	(5)
Balance at End of Period	2,920	128	2,920	128
Change in Unrealized Incl in OCI	25		25
Liabilities
Balance at Beginning of Period	0		0	118
F&G Acquisition	2,857		2,857
Liabilities, Total Gains (Losses) Included in Earnings	100		100
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	2,957		2,957
Change in Unrealized Incl in OCI			0
Future policy benefits
Liabilities
Balance at Beginning of Period	0		0
F&G Acquisition	5		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	0		0
Liabilities, Settlements	0		0
Liabilities, Net transfer In (Out) of Level 3	0		0
Balance at End of Period	5		5
Change in Unrealized Incl in OCI	0		0
FIA embedded derivatives, included in contractholder funds
Liabilities
Balance at Beginning of Period	0		0
F&G Acquisition	2,852		2,852
Liabilities, Total Gains (Losses) Included in Earnings	100		100
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	2,952		2,952
Change in Unrealized Incl in OCI	0		0
Asset-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	854		854
Assets, Total Gains (Losses) Included in Earnings	0		0
Assets, Total Gains (Losses) Included in AOCI	9		9
Assets, Purchases	91		91
Assets, Sales	0		0
Assets, Settlements	(5)		(5)
Assets, Net transfer In (Out) of Level 3	67		67
Balance at End of Period	1,016		1,016
Change in Unrealized Incl in OCI	9		9
Commercial mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	26		26
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	26		26
Change in Unrealized Incl in OCI	0		0
Corporates
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	14	18	17	17
F&G Acquisition	1,238		1,238
Assets, Total Gains (Losses) Included in Earnings	0	0	(3)	1
Assets, Total Gains (Losses) Included in AOCI	26	0	26	(1)
Assets, Purchases	0	0	0	5
Assets, Sales	0	0	0	(1)
Assets, Settlements	(14)	0	(14)	0
Assets, Net transfer In (Out) of Level 3	0	(2)	0	(5)
Balance at End of Period	1,264	16	1,264	16
Change in Unrealized Incl in OCI	26		26
Hybrids
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	4		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	0		0
Assets, Net transfer In (Out) of Level 3	0		0
Balance at End of Period	4		4
Change in Unrealized Incl in OCI	0		0
Municipals
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	38		38
Assets, Total Gains (Losses) Included in Earnings	0		0
Assets, Total Gains (Losses) Included in AOCI	2		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	40		40
Change in Unrealized Incl in OCI	3		3
Residential mortgage-backed securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	534		534
Assets, Total Gains (Losses) Included in Earnings	0		0
Assets, Total Gains (Losses) Included in AOCI	(15)		(15)
Assets, Purchases	1		1
Assets, Sales	0		0
Assets, Settlements	(4)		(4)
Assets, Net transfer In (Out) of Level 3	(7)		(7)
Balance at End of Period	509		509
Change in Unrealized Incl in OCI	(13)		(13)
Foreign Governments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	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	0		0
Assets, Net transfer In (Out) of Level 3	0		0
Balance at End of Period	16		16
Change in Unrealized Incl in OCI	0		0
Equity securities
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	1		1
F&G Acquisition	1		1
Assets, Total Gains (Losses) Included in Earnings	(1)		(1)
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	1		1
Change in Unrealized Incl in OCI	0		0
Available-for-sale embedded derivative
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	20		20
Assets, Total Gains (Losses) Included in Earnings	1		1
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	21		21
Change in Unrealized Incl in OCI	0		0
Credit linked note
Fixed maturity securities available-for-sale:
Balance at Beginning of Period	0		0
F&G Acquisition	23		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 Incl in OCI	0		0
Other long-term investments
Fixed maturity securities available-for-sale:
Balance at Beginning of Period		107	120	101
F&G Acquisition			0
Assets, Total Gains (Losses) Included in Earnings		5	(61)	11
Assets, Total Gains (Losses) Included in AOCI		0	0	0
Assets, Purchases		0	0	0
Assets, Sales		0	0	0
Assets, Settlements		0	0	0
Assets, Net transfer In (Out) of Level 3		0	(59)	0
Balance at End of Period	$ 0	$ 112	0	$ 112
Change in Unrealized Incl in OCI			$ 0

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

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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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