CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Dec. 31, 2015
Income Statement [Abstract]
Revenue	$ 1,057,530	$ 830,437	$ 2,130,810	$ 1,652,879
Costs of revenue:
Direct costs	705,321	547,140	1,433,542	1,084,564
Indirect costs and selling expenses	253,822	213,144	511,160	418,844
Depreciation and amortization	18,132	14,670	36,195	29,481
Total costs of revenue	977,275	774,954	1,980,897	1,532,889
Income from operations	80,255	55,483	149,913	119,990
Interest expense and other, net	12,325	8,180	24,814	17,362
Income before income taxes	67,930	47,303	125,099	102,628
Income taxes	25,510	16,851	46,016	37,544
Net income	$ 42,420	$ 30,452	$ 79,083	$ 65,084
Basic earnings per share	$ 1.74	$ 1.26	$ 3.25	$ 2.69
Diluted earnings per share	$ 1.69	$ 1.23	$ 3.16	$ 2.63
Weighted-average basic shares outstanding	24,387	24,246	24,363	24,227
Weighted-average diluted shares outstanding	25,069	24,786	24,998	24,754