Consolidated Statements of Changes in Shareholder's Equity - USD ($) $ in Millions	Total	Common stock	Additional paid-in capital	Retained earnings	Accumulated other comprehensive income/(loss)	Noncontrolling interests
Balance at Dec. 31, 2018	$ 2,849	$ 745	$ 2	$ 2,874	$ (925)	$ 153
Increase (Decrease) in Shareholder's Equity [Roll Forward]
Profit of consolidated companies	104			98		6
Foreign currency translation, net of tax	15				13	2
Derivative financial instruments, net of tax	(14)				(14)
Adjustment to adopt new accounting guidance | Accounting Standards Update 2018-02	0			(97)	97
Balance at Mar. 31, 2019	2,954	745	2	2,875	(829)	161
Balance at Dec. 31, 2019	3,236	745	2	3,162	(845)	172
Increase (Decrease) in Shareholder's Equity [Roll Forward]
Profit of consolidated companies	94			90		4
Foreign currency translation, net of tax	(307)				(306)	(1)
Derivative financial instruments, net of tax	6				6
Adjustment to adopt new accounting guidance | Accounting Standards Update 2016-13	(13)			(13)
Balance at Mar. 31, 2020	$ 3,016	$ 745	$ 2	$ 3,239	$ (1,145)	$ 175