Revenue from Contracts With Customers - Contract balances (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Contract with Customer, Contract Asset, Contract Liability, and Receivable [Abstract]
Contract assets	$ 0		$ 0		$ 0
Contract Liabilities (Current)	226,000,000		226,000,000		108,000,000
Contract Liabilities (Noncurrent)	35,000,000		35,000,000		$ 29,000,000
Increase (decrease) current contract liabilities			118,000,000
Increase (decrease) noncurrent contract liabilities			6,000,000
Total increase (decrease) in contract liabilities			124,000,000
Cash received on contract liabilities			503,000,000
Revenue recognized as sales			379,000,000
Revenue recognized from opening balance of contract liabilities			108,000,000
Revenue recognized from obligations satisfied or partially satisfied in prior periods	$ 7,000,000	$ (9,000,000)	$ 18,000,000	$ 12,000,000