Revenue Recognition - Customer Receivables and Contract Balances (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Capitalized Contract Cost [Line Items]
Customer receivables	$ 640	$ 683
Contract assets	35	38
Contract liabilities	247	385	$ 423
Accounts receivable, gross	679	728
Allowance for credit loss	39	$ 45
Disposal Group, Held-for-sale, Not Discontinued Operations
Capitalized Contract Cost [Line Items]
Customer receivables	83
Contract assets	0
Contract liabilities	$ 58