Consolidated Statements Of Stockholders' Equity - USD ($) $ in Millions	Preferred Stock [Member]	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Other comprehensive income (loss), net of tax				$ 9,984
Balance at Dec. 31, 2021		$ 4,735	$ 5,196	9,984
Stock compensation/issued for benefit plans		15
Net income (loss)			2,321		$ 2,321
Retirement of common stock/cancellation of shares		(204)	(296)
Common stock dividends declared			(156)
Other comprehensive income (loss), net of tax				(12,264)	(12,264)
Balance at Jun. 30, 2022		4,546	7,065	(2,280)	9,331
Balance at Mar. 31, 2022		4,586	6,354	3,315
Stock compensation/issued for benefit plans		9
Net income (loss)			840		840
Retirement of common stock/cancellation of shares		(49)	(51)
Common stock dividends declared			(78)
Other comprehensive income (loss), net of tax				(5,595)	(5,595)
Balance at Jun. 30, 2022		4,546	7,065	(2,280)	9,331
Balance at Dec. 31, 2022	$ 986	4,544	5,924	(6,352)	5,102
Stock compensation/issued for benefit plans		31
Net income (loss)			(370)		(370)
Preferred stock dividends declared			(36)
Common stock dividends declared			(156)
Other comprehensive income (loss), net of tax				1,248	1,248
Balance at Jun. 30, 2023	986	4,575	5,362	(5,104)	5,819
Balance at Mar. 31, 2023	986	4,560	4,940	(3,754)
Stock compensation/issued for benefit plans		15
Net income (loss)			511		511
Preferred stock dividends declared			(11)
Common stock dividends declared			(78)
Other comprehensive income (loss), net of tax				(1,350)	(1,350)
Balance at Jun. 30, 2023	$ 986	$ 4,575	$ 5,362	$ (5,104)	$ 5,819