Consolidated Statements of Stockholders' Equity - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance at Dec. 31, 2019	$ 34,232	$ 9,762	$ 209	$ (10,653)	$ 14,955	$ 20,180	$ (221)
Increase (Decrease) in Stockholders' Equity
Net income (loss)	(14,831)					(14,831)
Other comprehensive income (loss), net of tax	(67)						(67)
Dividends on common stock	(746)					(746)
Dividends on preferred stock	(400)		6		438	(844)
Shareholder warrants exercised	4				767	(763)
Berkshire Warrants	103				103
Issuance of common stock and other, net	290		1		289
Purchases of treasury stock	(12)			(12)
Ending balance at Dec. 31, 2020	18,573	9,762	216	(10,665)	16,552	2,996	(288)
Increase (Decrease) in Stockholders' Equity
Net income (loss)	2,322					2,322
Other comprehensive income (loss), net of tax	80						80
Dividends on common stock	(38)					(38)
Dividends on preferred stock	(800)					(800)
Shareholder warrants exercised	7				7
Issuance of common stock and other, net	191		1		190
Purchases of treasury stock	(8)			(8)
Ending balance at Dec. 31, 2021	20,327	9,762	217	(10,673)	16,749	4,480	(208)
Increase (Decrease) in Stockholders' Equity
Net income (loss)	13,304					13,304
Other comprehensive income (loss), net of tax	403						403
Dividends on common stock	(485)					(485)
Dividends on preferred stock	(800)					(800)
Shareholder warrants exercised	254		2		252
Options Exercised	27				27
Issuance of common stock and other, net	154		1		153
Purchases of treasury stock	(3,099)			(3,099)
Ending balance at Dec. 31, 2022	$ 30,085	$ 9,762	$ 220	$ (13,772)	$ 17,181	$ 16,499	$ 195