Other (Income) Expense - Narrative (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Other Income and Expenses [Abstract]
Gain (loss) related to settlement		$ 69
Interest income, tax settlement	$ 0	$ 48		$ 0	$ 48	$ 0
Net foreign currency exchange (gains) losses include expense related to out of period adjustment			$ 7
Write off of previously capitalized Bridge Facility fees					10
Gain (Loss) on Disposition of Assets	$ (10)			$ 0	$ (10)	$ 2