Accumulated Other Comprehensive Income (Loss) - Summary of AOCI(L) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	$ 3,030	$ 3,258
Other comprehensive income (loss)	(278)	35
Ending balance	2,284	3,200
Accumulated Other Comprehensive Income Attributable to Parent
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Beginning balance	(1,705)	(1,677)
Ending balance	(1,983)	(1,642)
Accumulated Foreign Currency Adjustment Attributable to Parent
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), adjustments during the period	(272)	43
Income taxes	(15)	(12)
Other comprehensive income (loss)	(287)	31
Accumulated Defined Benefit Plans Adjustment Attributable to Parent
Changes in Accumulated Other Comprehensive Income [Roll Forward]
Other comprehensive income (loss), adjustments reclassified to income	12	5
Income taxes	(3)	(1)
Other comprehensive income (loss)	$ 9	$ 4