Shareholders' Equity - Changes in AOCI Components (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022		Sep. 30, 2023		Sep. 30, 2022
Changes in balances of each component of AOCI, net of tax
Beginning balance	$ 4,080	$ 4,070		$ 3,803	[1]	$ 4,837
OCI before reclassifications	(521)	(985)		(317)		(2,087)
Amounts reclassified from AOCI	30	68		23		64
Total other comprehensive income (loss), net of tax	(491)	(917)	[2]	(294)		(2,023)	[2]
Ending balance	3,825	3,618	[3]	3,825		3,618	[3]
Total AOCI
Changes in balances of each component of AOCI, net of tax
Beginning balance	(2,349)	(1,748)		(2,546)		(642)
Total other comprehensive income (loss), net of tax	(491)	(917)		(294)		(2,023)
Ending balance	(2,840)	(2,665)	[3]	(2,840)		(2,665)	[3]
Net unrealized gains (losses) on securities
Changes in balances of each component of AOCI, net of tax
Beginning balance	(1,951)	(1,254)		(2,043)		1,033
OCI before reclassifications	(653)	(1,097)		(554)		(3,380)
Amounts reclassified from AOCI	30	68		23		64
Total other comprehensive income (loss), net of tax	(623)	(1,029)		(531)		(3,316)
Ending balance	(2,574)	(2,283)		(2,574)		(2,283)
Net unrealized gains (losses) on derivatives
Changes in balances of each component of AOCI, net of tax
Beginning balance	5	3		3		4
OCI before reclassifications	0	0		2		(1)
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	0	0		2		(1)
Ending balance	5	3		5		3
Effect of changes in discount rate assumptions on certain long-duration contracts
Changes in balances of each component of AOCI, net of tax
Beginning balance	(78)	(243)		(72)		(933)
OCI before reclassifications	174	241		168		931
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	174	241		168		931
Ending balance	96	(2)		96		(2)
Effect of changes in instrument-specific credit risk on MRBs
Changes in balances of each component of AOCI, net of tax
Beginning balance	15	233		(20)		(427)
OCI before reclassifications	18	(3)		53		657
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	18	(3)		53		657
Ending balance	33	230		33		230
Defined benefit plans
Changes in balances of each component of AOCI, net of tax
Beginning balance	(75)	(151)		(75)		(151)
OCI before reclassifications	0	1		0		1
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	0	1		0		1
Ending balance	(75)	(150)		(75)		(150)
Foreign currency translation
Changes in balances of each component of AOCI, net of tax
Beginning balance	(264)	(335)		(338)		(167)
OCI before reclassifications	(60)	(127)		14		(295)
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	(60)	(127)		14		(295)
Ending balance	(324)	(462)		(324)		(462)
Other
Changes in balances of each component of AOCI, net of tax
Beginning balance	(1)	(1)		(1)		(1)
OCI before reclassifications	0	0		0		0
Amounts reclassified from AOCI	0	0		0		0
Total other comprehensive income (loss), net of tax	0	0		0		0
Ending balance	$ (1)	$ (1)		$ (1)		$ (1)

[1] Certain prior period amounts have been restated. See Note 3 for more information.

[2] Certain prior period amounts have been restated. See Note 3 for more information.

[3] Certain prior period amounts have been restated. See Note 3 for more information.