Increase (Decrease) In Income From Change In Contract Estimates

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Increase (Decrease) In Income From Change In Contract Estimates Per Diluted Share

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Significant Accounting Policies [Line Items]

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payments on the derivative liability.

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-Glossary Notional Amount
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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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-Name Accounting Standards Codification
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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Glossary Income Tax Expense (or Benefit)
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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Fair value portion of an agreement for an unconditional promise by the maker to pay the holder a definite sum of money at a future date.

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Summary of Significant Accounting Policies (Additional Information) (Detail) - USD ($)	3 Months Ended		6 Months Ended
	Jul. 01, 2016	Jul. 03, 2015	Jul. 01, 2016	Jul. 03, 2015	Jan. 01, 2016
Significant Accounting Policies [Line Items]
Increase (decrease) in income due to contract estimates	$ 5,000,000	$ 5,000,000	$ 13,000,000	$ 10,000,000
Increase (decrease) in income due to contract estimates per diluted share	$ 0.04	$ 0.04	$ 0.11	$ 0.08
Income tax expense	$ 19,000,000	$ 15,000,000	$ 44,000,000	$ 15,000,000
Cash flows provided by operating activities of continuing operations			58,000,000	109,000,000
Cash flows used in financing activities of continuing operations			$ (61,000,000)	(206,000,000)
Leidos, Inc.
Significant Accounting Policies [Line Items]
Ownership interest (in percentage)	100.00%		100.00%
Income tax expense	$ 20,000,000	$ 17,000,000	$ 46,000,000	18,000,000
Cash flows provided by operating activities of continuing operations			58,000,000	109,000,000
Cash flows used in financing activities of continuing operations			(2,000,000)	$ (47,000,000)
Notes payable and long-term debt, net of current portion \| Designated as Hedging Instrument \| Interest rate swaps
Significant Accounting Policies [Line Items]
Fair value of long term debt	23,000,000		23,000,000		$ 8,000,000
Notes payable and long-term debt, net of current portion \| Notes Which Mature In December 2020 \| Designated as Hedging Instrument \| Interest rate swaps
Significant Accounting Policies [Line Items]
Hedged instrument, face amount	$ 450,000,000		$ 450,000,000
Stated interest rate (in percentage)	4.45%		4.45%
Fair value
Significant Accounting Policies [Line Items]
Fair value of long term debt	$ 1,060,000,000		$ 1,060,000,000
Carrying value
Significant Accounting Policies [Line Items]
Fair value of note receivable	95,000,000		95,000,000
Fair value of long term debt	1,090,000,000		1,090,000,000
Accounting Standards Update 2015-03 \| Notes payable and long-term debt, net of current portion
Significant Accounting Policies [Line Items]
Debt issuance costs					$ 7,000,000
Accounting Standards Update 2016-09, Excess Tax Benefit Component \| New Accounting Pronouncement, Early Adoption, Effect
Significant Accounting Policies [Line Items]
Effective income tax rate reconciliation, share-based compensation, excess tax benefit, amount	$ 3,000,000		7,000,000
Cash flows provided by operating activities of continuing operations			7,000,000
Cash flows used in financing activities of continuing operations			$ (7,000,000)