Statement of Changes in Consolidated Equity (unaudited) - USD ($) $ in Millions	Total	Preferred Class A	Preferred stock	Common stock	Additional capital	Accumulated deficit	Accumulated deficit Preferred Class A	Accumulated other comprehensive loss	Noncontrolling interests
Balance at beginning of period at Dec. 31, 2018	$ 5,585		$ 55	$ 483	$ 8,319	$ (358)		$ (2,926)	$ 12
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	187					187
Other comprehensive income (I)	76							76
Cash dividends declared:
Preferred dividends declared, value		$ (1)					$ (1)
Common share, value	(38)					(38)
Stock-based compensation	8				8
Common stock issued: compensation plans	(13)			2	(15)
Repurchase and retirement of common stock	(700)			(32)	(668)
Other	1					1
Balance at end of period at Mar. 31, 2019	$ 5,178		55	453	7,644	(134)		(2,852)	12
Cash dividends declared:
Preferred, dividends per share (in usd per share)		$ 0.9375
Common stock, dividends per share (in usd per share)	$ 0.08
Balance at beginning of period at Dec. 31, 2019	$ 4,621		55	433	7,319	129		(3,329)	14
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	215					215
Other comprehensive income (I)	(40)							(40)
Cash dividends declared:
Preferred dividends declared, value		$ (1)					$ (1)
Common share, value	(8)					(8)
Stock-based compensation	13				13
Common stock issued: compensation plans	(3)			3	(6)
Balance at end of period at Mar. 31, 2020	$ 4,797		$ 55	$ 436	$ 7,326	$ 335		$ (3,369)	$ 14
Cash dividends declared:
Preferred, dividends per share (in usd per share)		$ 0.9375
Common stock, dividends per share (in usd per share)	$ 0.02