Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Treasury Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning Balance (in shares) at Jul. 31, 2012		8,857,339	61,777,849
Beginning Balance at Jul. 31, 2012		$ (266,104)	$ 6,178	$ 192,248	$ 918,565	$ (60)
Net income	$ 152,862				152,862
Stock option and restricted stock activity (in shares)		941	203,951
Stock option and restricted stock activity		$ (43)	$ 21	5,783
Special dividend - $1.50 in 2013, $ 1.00 in 2014 per common share					(79,525)
Cash dividends - $.72 in 2013, $0.92 in 2014, $1.08 in 2015 per common share					(38,162)
Cashless exercises of stock options (in shares)	63,464		63,464
Cashless exercises of stock options			$ 6	(2,009)
Unrealized appreciation on investments, net of tax	$ 38					38
Stock compensation expense				2,816
Ending Balance (in shares) at Jul. 31, 2013		8,858,280	62,045,264
Ending Balance at Jul. 31, 2013		$ (266,147)	$ 6,205	198,838	953,740	(22)
Net income	179,002				179,002
Stock option and restricted stock activity (in shares)		1,831	101,313
Stock option and restricted stock activity		$ (101)	$ 10	3,674
Restricted stock unit activity (in shares)		20,766	63,852
Restricted stock unit activity		$ (1,205)	$ 6	758
Special dividend - $1.50 in 2013, $ 1.00 in 2014 per common share					(53,290)
Cash dividends - $.72 in 2013, $0.92 in 2014, $1.08 in 2015 per common share					(49,024)
Unrealized appreciation on investments, net of tax	22					$ 22
Stock compensation expense				5,231
Ending Balance (in shares) at Jul. 31, 2014		8,880,877	62,210,429
Ending Balance at Jul. 31, 2014	977,697	$ (267,453)	$ 6,221	208,501	1,030,428
Net income	199,385				199,385
Shares purchased (in shares)		1,000,000
Shares purchased		$ (60,000)
Stock option and restricted stock activity (in shares)			5,000
Stock option and restricted stock activity			$ 1	140
Restricted stock unit activity (in shares)		30,597	90,608
Restricted stock unit activity		$ (1,562)	$ 9	122
Cash dividends - $.72 in 2013, $0.92 in 2014, $1.08 in 2015 per common share					(57,381)
Stock compensation expense				6,776
Ending Balance (in shares) at Jul. 31, 2015		9,911,474	62,306,037
Ending Balance at Jul. 31, 2015	$ 1,065,187	$ (329,015)	$ 6,231	$ 215,539	$ 1,172,432