CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Revenues	$ 1,583,980	$ 1,551,918	$ 4,560,656	$ 4,480,135
Costs of revenues:
Direct costs	1,022,181	1,000,235	2,970,370	2,887,300
Indirect costs and selling expenses	402,227	369,015	1,114,310	1,071,826
Depreciation and amortization	34,216	31,230	99,484	93,608
Total costs of revenues	1,458,624	1,400,480	4,184,164	4,052,734
Income from operations	125,356	151,438	376,492	427,401
Interest expense and other, net	9,084	8,954	30,491	28,021
Income before income taxes	116,272	142,484	346,001	399,380
Income taxes	20,855	22,140	72,176	78,914
Net income	$ 95,417	$ 120,344	$ 273,825	$ 320,466
Basic earnings per share	$ 4.08	$ 4.83	$ 11.67	$ 12.81
Diluted earnings per share	$ 4.04	$ 4.78	$ 11.56	$ 12.66
Weighted-average basic shares outstanding	23,409	24,935	23,457	25,026
Weighted-average diluted shares outstanding	23,616	25,166	23,687	25,307