Consolidated Statements of Cash Flow - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Cash flows from operating activities:
Net income	$ 219,783	$ 178,687	$ 180,025
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	48,893	53,726	56,728
Allowance for doubtful accounts	(578)	1,087	(356)
Impairment of long-lived assets	0	29,104	0
Stock-based payment compensation	18,154	22,099	19,557
Excess tax benefit from stock-based payment compensation	(2,971)	(2,289)	(6,097)
Gain on sale of property and equipment	(918)	(1,461)	(962)
Deferred income taxes	4,365	(10,838)	(3,605)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	(20,417)	(12,870)	(31,171)
Vehicle pooling costs	(891)	(3,613)	(3,626)
Inventories	(1,731)	4,012	(1,777)
Prepaid expenses and other current assets	69	(4,500)	(5,971)
Other assets	10,125	(8,900)	(18,714)
Accounts payable and accrued liabilities	(3,926)	5,425	14,749
Deferred revenue	(438)	(661)	(871)
Income taxes receivable	(806)	9,267	(752)
Income taxes payable	(1,971)	2,816	1,609
Other liabilities	(1,666)	1,503	560
Net cash provided by operating activities	265,076	262,594	199,326
Cash flows from investing activities:
Purchases of property and equipment	(79,153)	(81,510)	(130,265)
Proceeds from sale of property and equipment	1,521	2,849	3,077
Proceeds from sale of assets held for sale	217	858	3,189
Investment in unconsolidated affiliate	(4,500)	0	0
Purchases of assets and liabilities in connection with acquisition, net of cash acquired	0	(14,300)	(84,022)
Net cash used in investing activities	(81,915)	(92,103)	(208,021)
Cash flows from financing activities:
Proceeds from the exercise of stock options	3,634	10,412	21,442
Excess tax benefit from stock-based payment compensation	2,971	2,289	6,097
Proceeds from the issuance of Employee Stock Purchase Plan shares	3,079	2,339	1,948
Repurchases of common stock	(237,306)	(572)	(15,009)
Change in bank overdraft	0	(16,291)	16,291
Proceeds from the issuance of long-term debt, net of discount	698,939	0	0
Debt offering costs	(955)	0	0
Principal payments on long-term debt	(350,000)	(75,000)	(96,660)
Net cash provided by (used in) financing activities	120,362	(76,823)	(65,891)
Effect of foreign currency translation	(6,179)	1,369	(1,895)
Net increase (decrease) in cash and cash equivalents	297,344	95,037	(76,481)
Cash and cash equivalents at beginning of period	158,668	63,631	140,112
Cash and cash equivalents at end of period	456,012	158,668	63,631
Supplemental disclosure of cash flow information:
Interest paid	18,121	8,768	10,267
Income taxes paid, net of refunds	$ 109,925	$ 82,813	$ 95,182