Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2020	Jan. 31, 2019
Statement of Cash Flows [Abstract]
Net income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 386,887	$ 245,456
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization, including debt cost	48,097	42,487
Allowance for doubtful accounts	1,301	96
Equity in losses (earnings) of unconsolidated affiliates	3,124	(514)
Stock-based compensation	11,674	11,950
Gain on sale of property and equipment	(1,315)	(3,890)
Deferred income taxes	6,719	6,632
Changes in operating assets and liabilities:
Accounts receivable	(78,510)	(86,125)
Vehicle pooling costs	(13,921)	(20,218)
Inventories	2,765	(11,640)
Prepaid expenses and other current and non-current assets	7,184	(725)
Operating Lease, Payments, Use	(331)	0
Accounts payable and accrued liabilities	24,862	7,338
Deferred revenue	1,021	2,843
Income taxes receivable	(48,722)	15,286
Income taxes payable	5,794	6,890
Other liabilities	(371)	(662)
Net Cash Provided by (Used in) Operating Activities	356,920	215,204
Cash flows from investing activities:
Purchases of property and equipment	(400,352)	(136,727)
Proceeds from sale of property and equipment	1,639	17,488
Net Cash Provided by (Used in) Investing Activities	(398,713)	(119,239)
Cash flows from financing activities:
Proceeds from the exercise of stock options	32,594	5,220
Proceeds from the issuance of Employee Stock Purchase Plan shares	3,955	3,501
Repurchases of common stock	0	(364,997)
Payments for employee stock-based tax withholdings	101,422	27
Proceeds from (Repayments of) Lines of Credit	13,600	93,300
Net Cash Provided by (Used in) Financing Activities	(51,273)	(263,003)
Effect of foreign currency translation	258	692
Net decrease in cash and cash equivalents	(92,808)	(166,346)
Cash and cash equivalents at beginning of period	186,319	274,520
Cash and cash equivalents at end of period	93,511	108,174
Supplemental disclosure of cash flow information:
Interest Paid, Excluding Capitalized Interest, Operating Activities	9,007	9,018
Income taxes paid, net of refunds	$ 57,591	$ 39,327