Condensed Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2017	Apr. 01, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 74	$ 53
Other comprehensive income, net of taxes:
Foreign currency translation adjustments	11	2
Unrecognized gain on derivative instruments	1	0
Total other comprehensive income, net of taxes	12	2
Comprehensive income	86	55
Less: comprehensive income attributable to non-controlling interest, net of taxes	2	0
Comprehensive income attributable to Leidos common stockholders	$ 84	$ 55

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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