Recent Accounting Pronouncements - Narrative (Details) - USD ($) $ in Millions	Jan. 01, 2019	Dec. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset		$ 271	$ 0
Other current liabilities		647	567
Other long-term liabilities		91	$ 280
Operating Lease, Liability		$ 320
Operating Lease, Weighted Average Discount Rate, Percent		5.50%
Finance Lease, Weighted Average Discount Rate, Percent		4.80%
Operating Lease, Weighted Average Remaining Lease Term		5 years
Finance Lease, Weighted Average Remaining Lease Term		3 years
Lessee, Operating Lease, Lease Not yet Commenced, Liability		$ 15
Lessee, Operating Lease, Lease Not yet Commenced, Renewal Term		3 years
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract		10 years
New Lease Guidance [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating Lease, Right-of-Use Asset	$ 387
Other current liabilities	103
Other long-term liabilities	(21)
Operating Lease, Liability	316
Cumulative Effect on Retained Earnings, Net of Tax	$ (8)