Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Treasury Stock	Common Stock	Additional Paid-in Capital	Retained Earnings
Beginning Balance (in shares) at Jul. 31, 2015		9,911,474	62,306,037
Beginning Balance at Jul. 31, 2015		$ (329,015)	$ 6,231	$ 215,539	$ 1,172,432
Net income	$ 256,519				256,519
Restricted stock unit activity (in shares)		45,706	133,758
Restricted stock unit activity		$ (2,484)	$ 13	(430)
Cash dividends - $1.20 in 2016, $1.32 in 2017, $1.48 in 2018 per common share					(62,970)
Stock compensation expense				9,387
Ending Balance (in shares) at Jul. 31, 2016		9,957,180	62,439,795
Ending Balance at Jul. 31, 2016		$ (331,499)	$ 6,244	224,496	1,365,981
Net income	374,254				374,254
Restricted stock unit activity (in shares)		53,889	157,315
Restricted stock unit activity		$ (4,572)	$ 16	(1,471)
Cash dividends - $1.20 in 2016, $1.32 in 2017, $1.48 in 2018 per common share					(69,409)
Stock compensation expense				12,500
Ending Balance (in shares) at Jul. 31, 2017		10,011,069	62,597,110
Ending Balance at Jul. 31, 2017	1,576,540	$ (336,071)	$ 6,260	235,525	1,670,826
Net income	430,151				430,151
Restricted stock unit activity (in shares)		59,390	168,714
Restricted stock unit activity		$ (7,657)	$ 17	(321)
Cash dividends - $1.20 in 2016, $1.32 in 2017, $1.48 in 2018 per common share					(77,989)
Stock compensation expense				17,000
Ending Balance (in shares) at Jul. 31, 2018		10,070,459	62,765,824
Ending Balance at Jul. 31, 2018	$ 1,937,741	$ (343,728)	$ 6,277	$ 252,204	$ 2,022,988