Business Segments (Schedule of Segment Reporting Information by Segment) (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Apr. 01, 2016
Segment Reporting Information [Line Items]
Revenues	$ 2,580	$ 1,312
Operating income (loss)	141	89
Defense Solutions
Segment Reporting Information [Line Items]
Revenues	1,294	780
Operating income (loss)	79	71
Civil
Segment Reporting Information [Line Items]
Revenues	842	361
Operating income (loss)	54	22
Health
Segment Reporting Information [Line Items]
Revenues	443	171
Operating income (loss)	47	16
Corporate
Segment Reporting Information [Line Items]
Revenues	1	0
Operating income (loss)	$ (39)	$ (20)