QUARTERLY FINANCIAL DATA (UNAUDITED) - Schedule of Quarterly Condensed Financial Operating Results (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2019
Quarterly Financial Data [Abstract]
Revenue	$ 1,564,000	$ 1,551,918	$ 1,468,711	$ 1,459,506	$ 1,495,581	$ 1,465,600	$ 1,395,469	$ 1,363,392	$ 6,044,135	$ 5,720,042	$ 4,986,341
Income from operations	112,050	151,438	141,539	134,424	133,676	113,676	110,187	100,157	539,451	457,696	377,867
Net income	$ 136,977	$ 120,344	$ 106,478	$ 93,644	$ 93,731	$ 80,577	$ 79,195	$ 67,977	$ 457,443	$ 321,480	$ 265,604
Basic earnings per share	$ 5.82	$ 4.83	$ 4.22	$ 3.73	$ 3.74	$ 3.21	$ 3.16	$ 2.73	$ 18.52	$ 12.84	$ 10.70
Diluted earnings per share	$ 5.74	$ 4.78	$ 4.18	$ 3.67	$ 3.68	$ 3.16	$ 3.11	$ 2.66	$ 18.30	$ 12.61	$ 10.46
Weighted-average basic shares outstanding	23,552	24,935	25,225	25,099	25,089	25,078	25,065	24,894	24,705	25,031	24,833
Weighted-average diluted shares outstanding	23,856	25,166	25,451	25,486	25,496	25,478	25,435	25,532	24,992	25,485	25,395