Lease Commitments - Other Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Lessee, Lease, Description [Line Items]
Operating lease costs	$ 45	$ 91	$ 129	$ 182
Amortization of ROU assets	7	0	11	0
Interest on lease liabilities	3	0	6	0
Lease, Cost	220	171	476	355
Short-term lease cost	51	70	105	156
Variable lease cost	24	29	62	60
Operating cash flows			270	95
Investing cash flows			49	44
Financing cash flows			12	0
Cost of Sales
Lessee, Lease, Description [Line Items]
Operating lease costs	143	61	287	138
Selling, general and administrative expenses
Lessee, Lease, Description [Line Items]
Operating lease costs	$ 22	$ 19	$ 43	$ 35