Shareholders' Equity - Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	$ 181
Balance at end of period	209
Other comprehensive income (loss) attributable to noncontrolling interests	(6)	$ (20)
Accumulated Other Comprehensive Income (Loss)
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	(744)	(711)
Balance at end of period	(789)	(908)
Foreign currency translation adjustments:
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	(395)	(369)
Other comprehensive income (loss) before reclassifications	(46)	(199)
Reclassification from other comprehensive income (loss)	0	0
Other comprehensive income (loss)	(46)	(199)
Income tax benefit (provision)	0	0
Balance at end of period	(441)	(568)
Defined benefit plans:
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	(353)	(342)
Other comprehensive income (loss) before reclassifications	4	0
Reclassification from other comprehensive income (loss)	0	3
Other comprehensive income (loss)	4	3
Income tax benefit (provision)	(1)	1
Balance at end of period	(350)	(338)
Cash flow hedges:
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance at beginning of period	4	0
Other comprehensive income (loss) before reclassifications	2	(3)
Reclassification from other comprehensive income (loss)	(4)	0
Other comprehensive income (loss)	(2)	(3)
Income tax benefit (provision)	0	1
Balance at end of period	$ 2	$ (2)