Acquisitions and Divestitures, Discontinued Operations (Details) - USD ($) $ in Millions			12 Months Ended
		Feb. 01, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Discontinued Operations [Abstract]
Proceeds from sale of discontinued operations				$ 358
Net sales				209
Income (loss) from discontinued operations, net of income taxes			$ 63	(522)	$ 32
Gain (loss) on sale of business	[1]		0	(31)	0
Assets [Abstract]
Current assets			0	664	1,262
Liabilities [Abstract]
Current liabilities			0	220
NSS [Member]
Discontinued Operations [Abstract]
Net sales			86	1,088	1,138
Cost of sales			(92)	(1,040)	(1,065)
Gain related to business diverstiture	[2]		64	0	0
Goodwill impairment charges			0	(571)	0
Operating income (loss) from discontinued operations			58	(523)	73
Interest expense allocated to discontinued operations			0	(20)	(20)
Income (loss) from discontinued operations before income taxes			58	(543)	53
Income tax benefit (expense)			5	21	(21)
Income (loss) from discontinued operations, net of income taxes			63	(522)	$ 32
NSS [Member] | Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operations [Abstract]
Gain (loss) on sale of business			$ 64
Assets [Abstract]
Current assets				201
Property, plant and equipment, net				25
Goodwill	[3]			390
Other assets				48
Total assets of discontinued operations				664
Liabilities [Abstract]
Accounts payable, trade				48
Other current liabilities				78
Current liabilities				126
Long-term liabilities				94
Total liabilities of discontinued operations				$ 220
CACI International Inc [Member] | Discontinued Operations, Disposed of by Sale [Member]
Discontinued Operations [Abstract]
Proceeds from sale of discontinued operations		$ 547

[1] See Note 3 for information regarding the Company's business divestitures.

[2] The year ended December 31, 2016 includes a gain of $64 million (before and after income taxes) on the sale of the NSS business.

[3] The goodwill balance at December 31, 2015 is based on an allocation of the goodwill attributable to the NSS reporting unit to discontinued operations based on the relative fair value of the NSS business retained by L3 and NSS business sold.