Restructuring and Other Charges (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019
Restructuring Cost and Reserve [Line Items]
Integration activities charges	$ 41	$ 181
Non-cash impairment charge	4	44
Accelerated amortization expense included within finance lease expense	17	62
Accelerated amortization expense	18	53
Employee Severance
Restructuring Cost and Reserve [Line Items]
Severance and other separation costs	28	105
Employee severance and other separation costs accrual	25	25	$ 14
Share-based compensation costs	$ 9	$ 32