Adoption of ASU 2018-12 (Summary of Restated Consolidated Statements of Stockholders Equity) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Dec. 31, 2021
Balance			$ 5,102
Net income (loss)	$ 511	$ 840	(370)	$ 2,321
Other comprehensive income (loss), net of tax	(1,350)	(5,595)	1,248	(12,264)
Balance	5,819	9,331	5,819	9,331
Retained Earnings [Member]
Balance	4,940	6,354	5,924	5,196
Net income (loss)	511	840	(370)	2,321
Balance	5,362	7,065	5,362	7,065	$ 5,196
Retirement of common stock/cancellation of shares		(51)		(296)
Common stock dividends declared	(78)	(78)	(156)	(156)
Accumulated Other Comprehensive Income (Loss) [Member]
Balance	(3,754)	3,315	(6,352)	9,984
Other comprehensive income (loss), net of tax	(1,350)	(5,595)	1,248	(12,264)	9,984
Balance	$ (5,104)	(2,280)	(5,104)	(2,280)	9,984
Accounting Standards Update 2018-12 [Member]
Net income (loss)		840
Other comprehensive income (loss), net of tax		(5,595)
Balance		9,331		9,331
Accounting Standards Update 2018-12 [Member] | Retained Earnings [Member]
Balance		6,354
Net income (loss)		840
Balance		7,065		7,065
Accounting Standards Update 2018-12 [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Balance		3,315
Other comprehensive income (loss), net of tax		(5,595)
Balance		(2,280)		(2,280)
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member]
Balance			4,569
Net income (loss)		228		319
Other comprehensive income (loss), net of tax		(5,589)		(10,778)
Balance		9,654		9,654
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member] | Retained Earnings [Member]
Balance		9,346		9,578
Net income (loss)		228		319
Balance		9,445		9,445	9,578
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Balance		1,252
Other comprehensive income (loss), net of tax		(5,589)		(10,778)	6,441
Balance		(4,337)		(4,337)
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member]
Balance			$ 533
Net income (loss)		612		2,002
Other comprehensive income (loss), net of tax		(6)		(1,486)
Balance		(323)		(323)
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member] | Retained Earnings [Member]
Balance		(2,992)		(4,382)
Net income (loss)		612		2,002
Balance		(2,380)		(2,380)	(4,382)
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Balance		2,063
Other comprehensive income (loss), net of tax		(6)		(1,486)	$ 3,543
Balance		$ 2,057		$ 2,057