Condensed Consolidated Statement of Changes in Equity - USD ($) $ in Millions	Total	Series B Preferred Stock	Series C Preferred Stock	Common stock and paid-in capital	Preferred stock	Preferred stock Series B Preferred Stock	Preferred stock Series C Preferred Stock	Accumulated deficit	Accumulated deficit Series B Preferred Stock	Accumulated deficit Series C Preferred Stock	Accumulated other comprehensive income (loss)	Treasury stock
Beginning balance at Dec. 31, 2020	$ 14,703			$ 21,544	$ 0			$ (4,278)			$ 631	$ (3,194)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,696							1,696
Net proceeds from issuance of series preferred stock		$ 1,335	$ 989			$ 1,335	$ 989
Share-based compensation	87			87
Other comprehensive income (loss)	(415)										(415)
Common stock repurchases	(721)											(721)
Common stock dividends	(144)							(144)
Ending balance at Jun. 30, 2021	17,530			21,631	2,324			(2,726)			216	(3,915)
Beginning balance at Mar. 31, 2021	14,625			21,566	0			(3,555)			27	(3,413)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	900							900
Net proceeds from issuance of series preferred stock		1,335	989			$ 1,335	$ 989
Share-based compensation	65			65
Other comprehensive income (loss)	189										189
Common stock repurchases	(502)											(502)
Common stock dividends	(71)							(71)
Ending balance at Jun. 30, 2021	17,530			21,631	2,324			(2,726)			216	(3,915)
Beginning balance at Dec. 31, 2021	17,050			21,671	2,324			(1,599)			(158)	(5,188)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	1,137							1,137
Share-based compensation	91			91
Other comprehensive income (loss)	(2,851)										(2,851)
Common stock repurchases	(1,184)											(1,184)
Common stock dividends	(203)							(203)
Preferred stock dividends		(32)	(24)						$ (32)	$ (24)
Ending balance at Jun. 30, 2022	13,984			21,762	2,324			(721)			(3,009)	(6,372)
Beginning balance at Mar. 31, 2022	15,413			21,728	2,324			(1,076)			(1,791)	(5,772)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	482							482
Share-based compensation	34			34
Other comprehensive income (loss)	(1,218)										(1,218)
Common stock repurchases	(600)											(600)
Common stock dividends	(99)							(99)
Preferred stock dividends		$ (16)	$ (12)						$ (16)	$ (12)
Ending balance at Jun. 30, 2022	$ 13,984			$ 21,762	$ 2,324			$ (721)			$ (3,009)	$ (6,372)