Derivative Financial Instruments - Summary of Effect of Foreign Currency Exchange Contracts (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Gains (losses) recognized in AOCI	$ (52)	$ 69	$ (28)	$ 98
Gains (losses) reclassified from AOCI into product sales	12	31	57	96
Gains (losses) recognized in Other income (expense), net	$ (13)	$ 40	$ (10)	$ 29