Related Party Transactions (Additional Information) (Detail)	6 Months Ended
Jul. 01, 2016 USD ($)
Leidos
Related Party Transaction [Line Items]
Renewal term ( in years)	1 year
Leidos, Inc.
Related Party Transaction [Line Items]
Credit facility, maturity date	2018
Notes receivable	$ 1,600,000,000
Notes Which Mature In December 2020 \| Leidos, Inc.
Related Party Transaction [Line Items]
Notes payable	$ 450,000,000
Stated interest rate (in percentage)	4.45%
Notes Which Mature In December 2040 \| Leidos, Inc.
Related Party Transaction [Line Items]
Notes payable	$ 300,000,000
Stated interest rate (in percentage)	5.95%
Notes Which Mature In July 2033 \| Leidos
Related Party Transaction [Line Items]
Notes payable	$ 300,000,000
Stated interest rate (in percentage)	5.50%
Notes Which Mature In July 2032 \| Leidos
Related Party Transaction [Line Items]
Notes payable	$ 250,000,000
Stated interest rate (in percentage)	7.13%

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