Summary of Significant Accounting Policies (Additional Information) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended			4 Months Ended	9 Months Ended		3 Months Ended		9 Months Ended		3 Months Ended	9 Months Ended		9 Months Ended
	Oct. 31, 2014	Aug. 01, 2014	Nov. 01, 2013	Jan. 31, 2014	Oct. 31, 2014	Nov. 01, 2013	Oct. 31, 2014 Leidos, Inc.	Nov. 01, 2013 Leidos, Inc.	Oct. 31, 2014 Leidos, Inc.	Nov. 01, 2013 Leidos, Inc.	Nov. 01, 2013 SAIC	Nov. 01, 2013 SAIC	Sep. 19, 2013 SAIC	Oct. 31, 2014 One Customer project
Significant Accounting Policies [Line Items]
Ownership interest							100.00%		100.00%
Reverse stock split				0.25
Stock issued to Leidos shareholder upon divestiture of SAIC, ratio													1.4285
Restructuring charges, net					$ 1						$ 20	$ 55
Outstanding receivables														28
Allowance for outstanding receivable														7
Number of projects														1
Increase (decrease) in income due to contract estimates	6		(1)		24	(29)
Increase (decrease) in income due to contract estimates per diluted share	$ (0.05)		$ 0.02		$ (0.20)	$ 0.22
Goodwill impairment charges	$ 0	$ 486	$ 0		$ 486	$ 0	$ 0	$ 0	$ 486	$ 0