Information on Business Segments - Summary of Financial Information for Each Business Segment (Detail) - USD ($) $ in Millions	3 Months Ended									12 Months Ended
	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 24, 2018	Mar. 25, 2018	Mar. 26, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Net sales
Net sales	$ 15,878	$ 15,171	$ 14,427	$ 14,336	$ 14,411	$ 14,318	$ 13,398	$ 11,635		$ 59,812	$ 53,762	$ 49,960
Operating profit
Operating profit	$ 2,149	$ 2,105	$ 2,008	2,283	1,851	$ 1,963	1,795	$ 1,725		8,545	7,334	6,744
Unallocated items
Severance and restructuring charges										0	96	0
Gain on property sale										51	0	198
Net gain on divestiture of business segment										0	0	73
AMMROC
Unallocated items
Equity method investee impairment					$ 110				$ 64
Land
Unallocated items
Gain on property sale				$ 51								198
Operating Segments
Net sales
Net sales										59,812	53,762	49,960
Operating profit
Operating profit										6,574	5,877	5,092
Segment Reconciling Items
Unallocated items
FAS/CAS operating adjustment										2,049	1,803	1,613
Stock-based compensation										189	173	158
Severance and restructuring charges										0	(96)	0
Other, net										111	(77)	197
Total unallocated, net										1,971	1,457	1,652
Aeronautics
Net sales
Net sales										23,693	21,242	19,410
Aeronautics | Operating Segments
Net sales
Net sales										23,693	21,242	19,410
Operating profit
Operating profit										2,521	2,272	2,176
Missiles and Fire Control
Net sales
Net sales										10,131	8,462	7,282
Missiles and Fire Control | Operating Segments
Net sales
Net sales										10,131	8,462	7,282
Operating profit
Operating profit										1,441	1,248	1,034
Rotary and Mission Systems
Net sales
Net sales										15,128	14,250	13,663
Unallocated items
Severance and restructuring charges							$ 96			60
Rotary and Mission Systems | Operating Segments
Net sales
Net sales										15,128	14,250	13,663
Operating profit
Operating profit										1,421	1,302	902
Space
Net sales
Net sales										10,860	9,808	9,605
Space | Operating Segments
Net sales
Net sales										10,860	9,808	9,605
Operating profit
Operating profit										1,191	$ 1,055	$ 980
Disposed of by Sale | Distributed Energy Solutions
Unallocated items
Net gain on divestiture of business segment										$ 34