Schedule of Segment Reporting Information by Segment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 31, 2014	Nov. 01, 2013	Oct. 31, 2014	Nov. 01, 2013
Segment Reporting Information [Line Items]
Revenues	$ 1,276	$ 1,414	$ 3,894	$ 4,464
Operating income (loss)	72	(5)	(251)	82
Segments | National Security Solutions
Segment Reporting Information [Line Items]
Revenues	906	1,011	2,775	3,107
Operating income (loss)	72	66	227	209
Segments | Health and Engineering
Segment Reporting Information [Line Items]
Revenues	373	406	1,126	1,368
Operating income (loss)	4	(30)	(455)	2
Segments | Corporate and Other
Segment Reporting Information [Line Items]
Revenues	(3)	(2)	(7)	(8)
Operating income (loss)	(4)	(41)	(23)	(129)
Intersegment Elimination
Segment Reporting Information [Line Items]
Revenues	$ 0	$ (1)	$ 0	$ (3)