Leases - Operating Lease Assets and Liabilities in the Consolidated Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Leases [Abstract]
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:OtherAssetsNoncurrent	us-gaap:OtherAssetsNoncurrent
Right-of-use assets classified in Other noncurrent assets	$ 123	$ 131
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other current liabilities	Other current liabilities
Current portion of lease liabilities classified in Other current liabilities	$ 36	$ 38
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other noncurrent liabilities and deferred credits	Other noncurrent liabilities and deferred credits
Long-term portion of lease liabilities classified in Other noncurrent liabilities	$ 93	$ 100
Total lease liabilities	$ 129	$ 138