Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Feb. 28, 2014	Feb. 28, 2013
Cash flows from operating activities
Net income	$ 12,315	$ 9,710
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	20,065	20,664
Stock-based compensation expense	1,839	1,948
Other	(2,321)	718
Decrease in operating assets:
Restricted cash	3,447	2,702
Accounts receivable and other assets	6,277	6,625
Increase (decrease) in operating liabilities:
Accounts payable	(2,216)	986
Accrued and other liabilities	(5,215)	(6,209)
Income taxes	1,729	(15,197)
Total adjustments	23,605	12,237
Net cash provided by operating activities	35,920	21,947
Cash flows from investing activities
Purchases of property and equipment	(31,587)	(13,917)
Proceeds from sale of assets	1,030	31,861
Other	3,002	1,977
Net cash provided by (used in) investing activities	(27,555)	19,921
Cash flows from financing activities
Payments on debt	(4,893)	(27,468)
Purchases of treasury stock	(57,847)	(25,550)
Proceeds from exercise of stock options	12,327	3,000
Other	(731)	(2,010)
Net cash used in financing activities	(51,144)	(52,028)
Net decrease in cash and cash equivalents	(42,779)	(10,160)
Cash and cash equivalents at beginning of period	77,896	52,647
Cash and cash equivalents at end of period	35,117	42,487
Cash paid during the period for:
Income taxes (net of refunds)	4,638	20,087
Non-cash investing and financing activities:
Change in obligation to acquire treasury stock	530	(1,102)
Notes receivable and direct financing leases from property disposition		$ 8,661