CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2011	Oct. 31, 2010
Cash flows from operating activities:
Net income	$ 41,149	$ 37,823
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	12,027	11,722
Allowance for doubtful accounts	(557)	(41)
Share-based compensation	5,045	4,636
Excess tax benefits from share-based compensation	(202)	(110)
(Gain)/Loss on sale and impairment of property and equipment	(288)	1,273
Changes in operating assets and liabilities:
Accounts receivable	(13,144)	(7,985)
Vehicle pooling costs	76	9,277
Inventories	1,447	739
Prepaid expenses and other current assets	3,499	2,819
Purchase of land options and other assets, net of proceeds	(4,165)	(60)
Accounts payable and accrued liabilities	207	353
Deferred revenue	(1,108)	(5,038)
Deferred income taxes	(3,572)	(395)
Income taxes receivable	4,572	8,690
Income taxes payable	18,727	13,923
Other liabilities	474	(88)
Net cash provided by operating activities	64,187	77,538
Cash flows from investing activities:
Purchases of property and equipment	(7,274)	(14,777)
Proceeds from sale of property and equipment	182	3,704
Net cash used in investing activities	(7,092)	(11,073)
Cash flows from financing activities:
Proceeds from the exercise of stock options	1,359	674
Excess tax benefit from share-based compensation	202	110
Repurchases of common stock	(43,983)	(75,710)
Proceeds from the issuance of long-term debt	125,000
Debt offering costs	(313)
Net cash provided by (used in) financing activities	82,265	(74,926)
Effect of foreign currency translation	(692)	743
Net increase (decrease) in cash and cash equivalents	138,668	(7,718)
Cash and cash equivalents at beginning of period	74,009	268,188
Cash and cash equivalents at end of period	212,677	260,470
Supplemental disclosure of cash flow information:
Interest paid	2,011	15
Income taxes paid	$ 2,998	$ 122