Account Values by Range of Guaranteed Minimum Crediting Rates (Details) - Investment contract reserves: - USD ($) $ in Millions	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022
Deferred Fixed Annuity
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	$ 680	$ 696	$ 734	$ 752	$ 755
Deferred Fixed Annuity | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	55			518
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	380			0
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	16			170
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	229			64
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	630			701
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	5			467
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	380			0
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	16			170
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	229			64
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	50			51
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	50			51
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	$ 456	$ 457	455	$ 457
Universal life | Policyholder Account Balance, at Guaranteed Minimum Crediting Rate
Policyholder Account Balance, Guaranteed Minimum Crediting Rate [Line Items]
Balance, end of period	396			399
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	0			46
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	57			8
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	3			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	120			115
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	60			59
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	0			46
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	57			8
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	3			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			52
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	54			52
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	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 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	282			288
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	282			288
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