Fair Value Measurements (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Liabilities [Abstract]
Contingent consideration		$ 29	$ 31	$ 29
Contingent Consideration, Liability [Abstract]
Balance at beginning of period		29
Acquisitions		14
Changes in fair value of contingent consideration, net		(12)
Balance at end of period		31
Recurring [Member] | Level 1 [Member]
Assets [Abstract]
Cash equivalents	[1]		310	104
Derivatives (foreign currency forward contracts)	[1]		0	0
Total assets	[1]		310	104
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[1]		0	0
Contingent consideration	[1],[2]	0	0	0
Total liabilities	[1]		0	0
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[1],[2]	0
Balance at end of period	[1],[2]	0
Recurring [Member] | Level 2 [Member]
Assets [Abstract]
Cash equivalents	[3]		0	0
Derivatives (foreign currency forward contracts)	[3]		11	12
Total assets	[3]		11	12
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[3]		1	6
Contingent consideration	[2],[3]	0	0	0
Total liabilities	[3]		1	6
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[2],[3]	0
Balance at end of period	[2],[3]	0
Recurring [Member] | Level 3 [Member]
Assets [Abstract]
Cash equivalents	[4]		0	0
Derivatives (foreign currency forward contracts)	[4]		0	0
Total assets	[4]		0	0
Liabilities [Abstract]
Derivatives (foreign currency forward contracts)	[4]		0	0
Contingent consideration	[2],[4]	29	31	29
Total liabilities	[4]		$ 31	$ 29
Contingent Consideration, Liability [Abstract]
Balance at beginning of period	[2],[4]	29
Balance at end of period	[2],[4]	$ 31

[1] Level 1 is based on quoted market prices available in active markets for identical assets or liabilities as of the reporting date. Cash equivalents are primarily held in registered money market funds, which are valued using quoted market prices.

[2] The contingent consideration liability represents the future potential earn-out payments relating to the L3 MacDonald Humfrey acquisition. The fair value of the contingent consideration liability is based on a Monte Carlo Simulation of the aggregate revenue of L3 MacDonald Humfrey for the three-year period ending December 31, 2019. The significant unobservable inputs used in calculating the fair value of the contingent consideration include: (i) projected revenues of the L3 MacDonald Humfrey acquired business, (ii) company specific risk premium, which is a component of the discount rate applied to the revenue projections, (iii) and volatility. The fair value of the contingent consideration for potential earn-out payments is reassessed quarterly, including an analysis of the significant inputs used in the evaluation, as well as the accretion of the present value discount. Changes are reflected within cost of sales in the consolidated statements of operations.

[3] Level 2 is based on pricing inputs other than quoted prices in active markets, which are either directly or indirectly observable. The fair value is determined using a valuation model based on observable market inputs, including quoted foreign currency forward exchange rates and consideration of non-performance risk.

[4] Level 3 is based on pricing inputs that are not observable and not corroborated by market data.