Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	May 31, 2013	May 31, 2012
Cash flows from operating activities
Net income	$ 24,503	$ 21,583
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	30,447	31,264
Stock-based compensation expense	2,812	3,204
Other	(53)	(1,162)
(Increase) decrease in operating assets:
Restricted cash	1,112	2,455
Accounts receivable and other assets	(209)	(611)
Increase (decrease) in operating liabilities:
Accounts payable	2,102	834
Accrued and other liabilities	2,797	(1,286)
Income taxes	(7,661)	7,665
Total adjustments	31,347	42,363
Net cash provided by operating activities	55,850	63,946
Cash flows from investing activities
Purchases of property and equipment	(28,378)	(12,938)
Proceeds from sale of assets	32,342	8,562
Other	140	(7,806)
Net cash provided by and (used in) investing activities	4,104	(12,182)
Cash flows from financing activities
Payments on debt	(31,076)	(11,271)
Purchases of treasury stock	(36,538)	(25,534)
Proceeds from exercise of stock options	11,181
Other	(2,614)	(2,796)
Net cash used in financing activities	(59,047)	(39,601)
Net increase in cash and cash equivalents	907	12,163
Cash and cash equivalents at beginning of period	52,647	29,509
Cash and cash equivalents at end of period	53,554	41,672
Non-cash investing and financing activities:
Change in obligation to acquire treasury stock	(1,058)
Notes receivable and direct financing leases from property disposition	$ 8,661