Goodwill and Identifiable Intangible Assets, Allocated by Reportable Segment (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($) Employee	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Goodwill [Line Items]
Approximate number of employees \| Employee	31,000
Goodwill [Roll Forward]
Goodwill	$ 6,904	$ 6,719	$ 6,478
Accumulated impairment losses	(104)	(104)	(104)
Balance, Beginning	6,615	6,374
Business acquisitions	247	212
Business divestitures		(12)
Foreign currency translation adjustments	(54)	93
Assets held for sale		(52)
Balance, Ending	6,808	6,615
ISR Systems [Member]
Goodwill [Roll Forward]
Goodwill	2,634	2,504	2,512
Accumulated impairment losses	(46)	(46)	(46)
Balance, Beginning	2,458	2,466
Business acquisitions	158	8
Business divestitures		0
Foreign currency translation adjustments	(20)	26
Assets held for sale		(42)
Balance, Ending	2,596	2,458
C&NS [Member]
Goodwill [Roll Forward]
Goodwill	2,022	1,977	1,883
Accumulated impairment losses	(15)	(15)	(15)
Balance, Beginning	1,962	1,868
Business acquisitions	56	73
Business divestitures		0
Foreign currency translation adjustments	(11)	21
Assets held for sale		0
Balance, Ending	2,007	1,962
Electronic Systems [Member]
Goodwill [Roll Forward]
Goodwill	2,248	2,238	2,083
Accumulated impairment losses	(43)	(43)	$ (43)
Balance, Beginning	2,195	2,040
Business acquisitions	33	131
Business divestitures		(12)
Foreign currency translation adjustments	(23)	46
Assets held for sale		(10)
Balance, Ending	$ 2,205	$ 2,195

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