SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) (DETAILS) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended				6 Months Ended
	Jul. 04, 2014		Jun. 28, 2013		Jul. 04, 2014		Jun. 28, 2013
Selected Quarterly Financial Information (unaudited) [Abstract]
Revenues	$ 2,555		$ 2,792		$ 5,092		$ 5,595
Cost of revenues	(2,407)		(2,642)		(4,854)		(5,293)
Operating income (loss)	138		145		225		298
Other income (expenses)	1		(3)		(3)		(6)
Income tax benefit (expense)	(13)		(39)		(39)		(81)
Net income (loss) including noncontrolling interests	108		82		147		169
Noncontrolling interests in income of consolidated subsidiaries	(20)		(15)		(32)		(30)
Net income (loss) attributable to URS	88		67		115		139
Earnings (loss) per share:
Basic	$ 1.28		$ 0.91		$ 1.64		$ 1.88
Diluted	$ 1.27		$ 0.91		$ 1.63		$ 1.87
Weighted-average shares of common stock outstanding:
Basic	68.3	[1]	73.8	[1]	69.9	[1]	74.1	[1]
Diluted	68.8		74.0		70.5		74.4
Selected Quarterly Financial Information (Textuals) [Abstract]
Effective income tax rate %	10.80%		32.30%		32.50%		20.70%
Consolidated Statements of Operations Data [Abstract]
Income (loss) before income taxes	121		121		186		250
Operating income (loss)	138		145		225		298
Income tax benefit (expense)	(13)		(39)		(39)		(81)
Net income (loss) including noncontrolling interests	108		82		147		169
Noncontrolling interests in income of consolidated subsidiaries	(20)		(15)		(32)		(30)
Net income (loss) attributable to URS	$ 88		$ 67		$ 115		$ 139

[1] Weighted-average shares of common stock outstanding are net of treasury stock and exclude nonvested restricted stock awards.