Progress Collections and Deferred Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Progress collections and deferred income (contract liabilities)	$ 2,870	$ 1,765
Revenue recognized, included in contract liability	1,690	1,392
Progress collections
Disaggregation of Revenue [Line Items]
Progress collections and deferred income (contract liabilities)	2,760	1,600
Deferred income
Disaggregation of Revenue [Line Items]
Progress collections and deferred income (contract liabilities)	$ 110	$ 165