CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Revenue	$ 1,086,418	$ 977,274	$ 3,217,228	$ 2,630,153
Costs of revenue:
Direct costs	732,224	647,489	2,165,766	1,732,053
Indirect costs and selling expenses	269,237	249,477	780,397	668,321
Depreciation and amortization	17,703	16,632	53,898	46,113
Total costs of revenue	1,019,164	913,598	3,000,061	2,446,487
Income from operations	67,254	63,676	217,167	183,666
Interest expense and other, net	12,107	11,115	36,921	28,477
Income before income taxes	55,147	52,561	180,246	155,189
Income taxes	14,790	18,445	60,806	55,989
Net income	$ 40,357	$ 34,116	$ 119,440	$ 99,200
Basic earnings per share	$ 1.65	$ 1.41	$ 4.90	$ 4.09
Diluted earnings per share	$ 1.61	$ 1.38	$ 4.77	$ 4.01
Weighted-average basic shares outstanding	24,419	24,277	24,382	24,243
Weighted-average diluted shares outstanding	25,106	24,801	25,034	24,769