Consolidated Statements of Cash Flow - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2014
Cash flows from operating activities:
Net income	$ 270,360	$ 219,783	$ 178,687
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including debt cost	49,643	48,893	53,726
Allowance for doubtful accounts	1,175	(578)	1,087
Impairment of long-lived assets	0	0	29,104
Income (Loss) from Equity Method Investments	895	0	0
Stock-based payment compensation	20,864	18,154	22,099
Excess tax benefit from stock-based payment compensation	0	(2,971)	(2,289)
Gain on sale of property and equipment	(54)	(918)	(1,461)
Deferred income taxes	5,740	4,365	(10,838)
Changes in operating assets and liabilities, net of effects from acquisitions:
Accounts receivable	(54,213)	(20,417)	(12,870)
Vehicle pooling costs	(4,137)	(891)	(3,613)
Inventories	(2,509)	(1,731)	4,012
Prepaid expenses and other current assets	(738)	69	(4,500)
Other assets	4,164	10,125	(8,900)
Accounts payable and accrued liabilities	48,347	(3,926)	5,425
Deferred revenue	983	(438)	(661)
Income taxes receivable	(12,649)	(806)	9,267
Income taxes payable	2,788	(1,971)	2,816
Other liabilities	1,839	(1,666)	1,503
Net cash provided by operating activities	332,498	265,076	262,594
Cash flows from investing activities:
Purchases of property and equipment	(173,917)	(79,153)	(81,510)
Proceeds from sale of property and equipment	562	1,521	2,849
Proceeds from sale of assets held for sale	100	217	858
Investment in unconsolidated affiliate	0	(4,500)	0
Purchases of assets and liabilities in connection with acquisition, net of cash acquired	0	0	(14,300)
Payments to Acquire Available-for-sale Securities	(21,119)	0	0
Proceeds from Sale of Available-for-sale Securities	21,498	0	0
Net cash used in investing activities	(172,876)	(81,915)	(92,103)
Cash flows from financing activities:
Proceeds from the exercise of stock options	13,240	3,634	10,412
Excess tax benefit from stock-based payment compensation	0	2,971	2,289
Proceeds from the issuance of Employee Stock Purchase Plan shares	3,369	3,079	2,339
Repurchases of common stock	(457,894)	(237,306)	(572)
Change in bank overdraft	0	0	(16,291)
Proceeds from the issuance of long-term debt, net of discount	93,468	698,939	0
Proceeds from (Repayments of) Lines of Credit	238,000	0	0
Debt offering costs	(1,179)	(955)	0
Principal payments on long-term debt	(337,500)	(350,000)	(75,000)
Net cash (used in) provided by financing activities	(448,496)	120,362	(76,823)
Effect of foreign currency translation	(11,289)	(6,179)	1,369
Net (decrease) increase in cash and cash equivalents	(300,163)	297,344	95,037
Cash and cash equivalents at beginning of period	456,012	158,668	63,631
Cash and cash equivalents at end of period	155,849	456,012	158,668
Supplemental disclosure of cash flow information:
Interest paid	23,606	18,121	8,768
Income taxes paid, net of refunds	$ 127,981	$ 109,925	$ 82,813