Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Apr. 30, 2018	Apr. 30, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 19,317	$ (49,618)
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (benefit from) deferred income taxes	4,209	(8,402)
Depreciation and amortization	16,151	19,221
Asset impairment charges		83,474
Share-based compensation expense	6,128	6,450
Amortization of demo equipment	2,133	1,557
Provision for excess and obsolete inventory	4,133	287
Excess tax benefit from share-based compensation		(158)
Change in fair value of contingent consideration		(10,238)
(Benefit from) provision for doubtful accounts, net of recovery	(406)	88
Gain/(Loss) on sale of property, plant and equipment	70	(57)
Net changes in operating assets and liabilities:
Accounts receivable	(6,367)	18,295
Inventory	(6,163)	(5,547)
Prepaid expenses and other assets	282	596
Accounts payable	9,259	608
Accrued liabilities	327	(2,845)
Deferred revenue	1,807	(641)
Customer deposits	(469)	554
Accrued income taxes and income taxes receivable	6,228	1,174
Other liabilities	1,060	(1,423)
Cash paid for contingent consideration		(100)
NET CASH PROVIDED BY OPERATING ACTIVITIES	57,699	53,275
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant, and equipment	(4,235)	(7,741)
Purchases of marketable securities	(91,942)
Proceeds from maturities of marketable securities	28,900
Proceeds from sales of marketable securities	9,254
Proceeds from the sale of property, plant, and equipment	1	30
NET CASH USED IN INVESTING ACTIVITIES	(58,022)	(7,711)
CASH FLOWS FROM FINANCING ACTIVITIES:
Issuance of stock pursuant to exercise of stock options, employee stock purchase plan, restricted stock plans, and non-employee director stock plan	832	3,090
Repurchase of common stock	(952)	(1,584)
Shares repurchased for taxes for vested employee restricted stock grants	(1,086)	(1,128)
Excess tax benefit from share-based compensation		158
Dividends paid to shareholders	(3,747)	(3,771)
Contingent consideration paid for business acquisitions		(1,900)
NET CASH USED IN FINANCING ACTIVITIES	(4,953)	(5,135)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	(83)	(493)
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(5,359)	39,936
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	129,298	118,697
CASH AND CASH EQUIVALENTS, END OF PERIOD	123,939	158,633
Supplemental disclosures of cash flow information:
Non-cash transfer of demonstration inventory to fixed asset	$ 2,263	$ 3,506