Consolidated Statements of Income (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Feb. 28, 2018	Feb. 28, 2017	Feb. 28, 2018	Feb. 28, 2017
Revenues	$ 335,231	$ 294,354	$ 664,372	$ 582,417
Operating expenses
Cost of services	163,232	131,635	324,756	258,885
Selling, general and administrative	76,514	70,973	155,033	141,467
Total operating expenses	239,746	202,608	479,789	400,352
Operating income	95,485	91,746	184,583	182,065
Other expense
Loss on sale of business		(1,208)		(1,223)
Interest expense, net of interest income	(3,272)	(1,048)	(6,191)	(1,532)
Total other expense	(3,272)	(2,256)	(6,191)	(2,755)
Income before income taxes	92,213	89,490	178,392	179,310
Provision for income taxes	39,076	22,780	54,876	46,017
Net income	$ 53,137	$ 66,710	$ 123,516	$ 133,293
Basic earnings per common share (in dollars per share)	$ 1.36	$ 1.69	$ 3.16	$ 3.36
Diluted earnings per common share (in dollars per share)	$ 1.33	$ 1.68	$ 3.11	$ 3.34
Basic weighted average common shares (in shares)	38,991	39,489	39,038	39,659
Diluted weighted average common shares (in shares)	39,846	39,700	39,763	39,900