Consolidated Statements of Income - Unaudited - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2023	Feb. 28, 2022	Feb. 28, 2023	Feb. 28, 2022
Income Statement [Abstract]
Revenues	$ 515,085	$ 431,119	$ 1,019,900	$ 855,844
Operating expenses
Cost of services	240,806	199,413	467,848	406,544
Selling, general and administrative	104,582	98,066	210,178	189,304
Asset impairments	447	10,292	729	13,987
Total operating expenses	345,835	307,771	678,755	609,835
Operating income	169,250	123,348	341,145	246,009
Other income (expense), net
Interest expense, net	(13,834)	(1,673)	(28,166)	(3,167)
Other income (expense), net	1,346	281	1,668	(956)
Total other income (expense), net	(12,488)	(1,392)	(26,498)	(4,123)
Income before income taxes	156,762	121,956	314,647	241,886
Provision for income taxes	25,169	12,018	46,256	24,301
Net income	$ 131,593	$ 109,938	$ 268,391	$ 217,585
Basic earnings per common share (in USD per share)	$ 3.44	$ 2.91	$ 7.03	$ 5.77
Diluted earnings per common share (in USD per share)	$ 3.38	$ 2.84	$ 6.89	$ 5.63
Basic weighted average common shares (in shares)	38,281	37,837	38,201	37,685
Diluted weighted average common shares (in shares)	38,981	38,761	38,947	38,628