CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Jul. 26, 2014	Apr. 26, 2014	Jan. 25, 2014	Oct. 26, 2013	Jul. 27, 2013	Apr. 27, 2013	Jan. 26, 2013	Oct. 27, 2012	Jul. 26, 2014	Jul. 27, 2013	Jul. 28, 2012
REVENUES:
Contract revenues	$ 482,071	$ 426,284	$ 390,518	$ 512,720	$ 478,632	$ 437,367	$ 369,326	$ 323,286	$ 1,811,593	$ 1,608,612	$ 1,201,119
EXPENSES:
Costs of earned revenues, excluding depreciation and amortization	387,221	350,352	327,353	410,119	384,169	357,664	301,516	257,066	1,475,045	1,300,416	968,949
General and administrative (including stock-based compensation expense of $12.6 million, $9.9 million and $7.0 million, respectively)									161,858	145,771	104,024
Depreciation and amortization									92,772	85,481	62,693
Total									1,729,675	1,531,668	1,135,666
Interest expense, net									(26,827)	(23,334)	(16,717)
Other income, net									11,228	4,589	15,825
INCOME BEFORE INCOME TAXES									66,319	58,199	64,561
PROVISION (BENEFIT) FOR INCOME TAXES:
Current									32,664	25,281	15,309
Deferred									(6,323)	(2,270)	9,874
Total									26,341	23,011	25,183
NET INCOME	$ 16,489	$ 7,895	$ (3,067)	$ 18,660	$ 14,666	$ 7,199	$ 1,463	$ 11,861	$ 39,978	$ 35,188	$ 39,378
EARNINGS PER COMMON SHARE:
Basic earnings per common share (usd per share)	$ 0.49	$ 0.23	$ (0.09)	$ 0.56	$ 0.44	$ 0.22	$ 0.04	$ 0.36	$ 1.18	$ 1.07	$ 1.17
Diluted earnings per common share (usd per share)	$ 0.47	$ 0.23	$ (0.09)	$ 0.54	$ 0.43	$ 0.21	$ 0.04	$ 0.35	$ 1.15	$ 1.04	$ 1.14
SHARES USED IN COMPUTING EARNINGS PER COMMON SHARE:
Basic (in shares)									33,773,158	33,012,595	33,653,055
Diluted (in shares)									34,816,381	33,782,187	34,481,895