Account Values by Range of Guaranteed Minimum Crediting Rates (Details) - Investment contract reserves: - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Deferred Fixed Annuity
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	$ 631	$ 656	$ 711
Deferred Fixed Annuity | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	53		59
Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	337		423
Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	15		17
Deferred Fixed Annuity | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	226		212
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	582		661
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	4		9
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	337		423
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	15		17
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	226		212
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	49		50
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	49		50
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Deferred Fixed Annuity | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Universal life
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	456	$ 457	458
Universal life | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	329		400
Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	65		47
Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	58		9
Universal life | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	4		2
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	122		118
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		60
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	60		47
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	58		9
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0200 to 0299 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	4		2
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	54		53
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	49		53
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	5		0
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0300 to 0399 | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	280		287
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	280		287
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0001 to 0050
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0051 to 0150
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	0		0
Universal life | Policyholder Account Balance, Guaranteed Minimum Crediting Rate, Range from 0400 and Greater | Policyholder Account Balance, above Guaranteed Minimum Crediting Rate, Range from 0151 and Greater
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	$ 0		$ 0