Cash and Equivalents (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Cash and Cash Equivalents [Line Items]
Cash and equivalents	$ 712	$ 739
Operating cash and equivalents
Cash and Cash Equivalents [Line Items]
Cash and equivalents	301	227
Short-term investments
Cash and Cash Equivalents [Line Items]
Cash and equivalents	151	194
Cash and equivalents held in consolidated joint ventures and Aspire Defence subcontracting entities
Cash and Cash Equivalents [Line Items]
Cash and equivalents	260	318
International
Cash and Cash Equivalents [Line Items]
Cash and equivalents	504	525
International | Operating cash and equivalents
Cash and Cash Equivalents [Line Items]
Cash and equivalents	187	123
International | Short-term investments
Cash and Cash Equivalents [Line Items]
Cash and equivalents	58	87
International | Cash and equivalents held in consolidated joint ventures and Aspire Defence subcontracting entities
Cash and Cash Equivalents [Line Items]
Cash and equivalents	259	315
Domestic
Cash and Cash Equivalents [Line Items]
Cash and equivalents	208	214
Domestic | Operating cash and equivalents
Cash and Cash Equivalents [Line Items]
Cash and equivalents	114	104
Domestic | Short-term investments
Cash and Cash Equivalents [Line Items]
Cash and equivalents	93	107
Domestic | Cash and equivalents held in consolidated joint ventures and Aspire Defence subcontracting entities
Cash and Cash Equivalents [Line Items]
Cash and equivalents	$ 1	$ 3