Receivables, net, Contract Assets and Contract Liabilities - Narrative (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
U.S. government receivables	$ 1,700
Receivables from other governments and commercial customers	2,337	$ 2,444
Contract assets, progress payments	33,000	30,200
Increase in contract assets	(378)	1,480	$ (390)
Impairment loss	0	0
Increase (decrease) in contract liability	563	(537)	353
Liability, revenue recognized	3,900	$ 3,900	$ 3,300
Other Governments and Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables from other governments and commercial customers	$ 648