Statement of Changes in Consolidated Equity (unaudited) - USD ($) $ in Millions	Total	Preferred Class A	Preferred stock	Common stock	Additional capital	Retained earnings	Retained earnings Preferred Class A	Accumulated other comprehensive loss	Noncontrolling Interests
Beginning balance at Dec. 31, 2019	$ 4,605		$ 55	$ 433	$ 7,319	$ 113		$ (3,329)	$ 14
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	215					215
Net income	215
Other comprehensive income (loss)	(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)
Ending balance at Mar. 31, 2020	4,781		55	436	7,326	319		(3,369)	$ 14
Beginning balance at Dec. 31, 2020	3,577		55	433	4,668	364		(1,943)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	80					80
Other comprehensive income (loss)	2							2
Cash dividends declared:
Preferred dividends declared, value		$ (1)					$ (1)
Stock-based compensation	6				6
Common stock issued: compensation plans	(2)			1	(3)
Ending balance at Mar. 31, 2021	$ 3,662		$ 55	$ 434	$ 4,671	$ 443		$ (1,941)