Consolidated Statements of Equity - USD ($) shares in Millions, $ in Millions	Total	Senior Preferred Stock	Preferred Stock, at Redemption Value	Common Stock, at Par Value	Additional Paid-In Capital	Retained Earnings (Accumulated Deficit)	AOCI, Net of Tax	Treasury Stock, at Cost
Beginning balance at Dec. 31, 2018	$ 4,477	$ 72,648	$ 14,109	$ 0	$ 0	$ (78,260)	$ (135)	$ (3,885)
Beginning balance, Shares at Dec. 31, 2018		1	464	650
Comprehensive income:
Net income (loss)	4,622					4,622
Other comprehensive income, net of taxes	717						717
Comprehensive income (loss)	5,339					4,622	717
Senior Preferred Stock Dividends Paid	(3,142)					(3,142)
Ending balance at Sep. 30, 2019	6,674	$ 72,648	$ 14,109	$ 0	0	(76,780)	582	(3,885)
Ending balance, Shares at Sep. 30, 2019		1	464	650
Beginning balance at Jun. 30, 2019	4,826	$ 72,648	$ 14,109	$ 0	0	(78,489)	443	(3,885)
Beginning balance, Shares at Jun. 30, 2019		1	464	650
Comprehensive income:
Net income (loss)	1,709					1,709
Other comprehensive income, net of taxes	139						139
Comprehensive income (loss)	1,848					1,709	139
Ending balance at Sep. 30, 2019	6,674	$ 72,648	$ 14,109	$ 0	0	(76,780)	582	(3,885)
Ending balance, Shares at Sep. 30, 2019		1	464	650
Comprehensive income:
Retained Earnings (Accumulated Deficit)	(74,188)
Beginning balance at Dec. 31, 2019	9,122	$ 72,648	$ 14,109	$ 0	0	(74,188)	438	(3,885)
Beginning balance, Shares at Dec. 31, 2019		1	464	650
Comprehensive income:
Net income (loss)	4,413					4,413
Other comprehensive income, net of taxes	596						596
Comprehensive income (loss)	5,009					4,413	596
Ending balance at Sep. 30, 2020	13,891	$ 72,648	$ 14,109	$ 0	0	(70,015)	1,034	(3,885)
Ending balance, Shares at Sep. 30, 2020		1	464	650
Beginning balance at Jun. 30, 2020	11,442	$ 72,648	$ 14,109	$ 0	0	(72,478)	1,048	(3,885)
Beginning balance, Shares at Jun. 30, 2020		1	464	650
Comprehensive income:
Net income (loss)	2,463					2,463
Other comprehensive income, net of taxes	(14)						(14)
Comprehensive income (loss)	2,449					2,463	(14)
Ending balance at Sep. 30, 2020	13,891	$ 72,648	$ 14,109	$ 0	$ 0	$ (70,015)	$ 1,034	$ (3,885)
Ending balance, Shares at Sep. 30, 2020		1	464	650
Comprehensive income:
Retained Earnings (Accumulated Deficit)	$ (70,015)