Accumulated Other Comprehensive Income (Loss) (AOCI) - Changes in AOCI by Component (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2020	Dec. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	$ (315)	$ (269)
Other comprehensive income (loss) before reclassifications	(43)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(3)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(46)
Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(303)	(260)
Other comprehensive income (loss) before reclassifications	(43)
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(43)
Changes in Employee Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	(12)	(10)
Other comprehensive income (loss) before reclassifications	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	(2)
Changes in Fair Value of Effective Cash Flow Hedges
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated other comprehensive loss	0	$ 1
Other comprehensive income (loss) before reclassifications	0
Reclassification from Accumulated Other Comprehensive Income, Current Period, Net of Tax	(1)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ (1)