Revenue Recognition - Summary of Balances of Accounts Receivable and Contract Assets, Net of Allowance for Credit Losses, from Contracts with Customers (Details) - USD ($) $ in Millions	Jun. 30, 2021	Dec. 31, 2020
Revenue From Contract With Customer [Abstract]
Accounts receivable	$ 114	$ 70
Contract assets	45	13
Total	$ 159	$ 83