Leases - Schedule of Cash Paid for Lease Liabilities and Right-of-Use Assets Obtained in Exchange for Lease Obligations (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Leases [Abstract]
Operating cash flows paid for operating leases	$ 52	$ 52
Financing cash flows paid for finance leases	1	1
Operating leases	$ 61	$ 34