Adoption of ASU 2018-12 (Summary of Restated Consolidated Statements of Stockholders Equity) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2021
Balance	$ 5,102
Net income (loss)	(881)	$ 1,482
Other comprehensive income (loss), net of tax	2,598	(6,669)
Balance	6,732	14,255
Retained Earnings [Member]
Balance	5,924	5,196
Net income (loss)	(881)	1,482
Balance	4,940	6,354	$ 5,196
Retirement of common stock/cancellation of shares		(245)
Common stock dividends declared	(78)	(79)
Accumulated Other Comprehensive Income (Loss) [Member]
Balance	(6,352)	9,984
Other comprehensive income (loss), net of tax	2,598	(6,669)	9,984
Balance	(3,754)	3,315	9,984
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member]
Balance	4,569
Net income (loss)		92
Other comprehensive income (loss), net of tax		(5,189)
Balance		15,184
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member] | Retained Earnings [Member]
Balance		9,578
Net income (loss)		92
Balance		9,346	9,578
Accounting Standards Update 2018-12 [Member] | As Previously Reported [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Other comprehensive income (loss), net of tax		(5,189)	6,411
Balance		1,252
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member]
Balance	$ 533
Net income (loss)		1,390
Other comprehensive income (loss), net of tax		(1,480)
Balance		(929)
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member] | Retained Earnings [Member]
Balance		(4,382)
Net income (loss)		1,390
Balance		(2,992)	(4,382)
Accounting Standards Update 2018-12 [Member] | Restatement Impacts [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Other comprehensive income (loss), net of tax		(1,480)	$ 3,573
Balance		$ 2,063