XML 67 R48.htm IDEA: XBRL DOCUMENT v3.20.4
Revenue Recognition - Contract with Customer, Asset and Liability (Details) - USD ($)
$ in Millions
Dec. 31, 2020
Dec. 31, 2019
Revenues [Abstract]    
Customer receivables $ 683 $ 678
Contract assets 38 32
Contract liabilities 385 423
Accounts receivable, gross 728 691
Allowance for credit loss $ 45 $ 13