Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 12,207	$ 10,046
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (benefit from) deferred income taxes	3,285	(194)
Depreciation and amortization	10,913	12,871
Asset impairment charges		10,423
Share-based compensation expense	3,881	4,255
Amortization of demo equipment	1,768	969
Provision for excess and obsolescence inventory	658	1,329
Excess tax benefit from share-based compensation		(158)
Change in fair value of contingent consideration		(8,103)
(Benefit from) provision for doubtful accounts, net of recovery	(245)	20
Loss on sale of property, plant and equipment	66	36
Net changes in operating assets and liabilities:
Accounts receivable	(5,681)	20,223
Inventory	2,794	(4,180)
Prepaid expenses and other assets	(87)	641
Accounts payable	1,013	1,207
Accrued liabilities	(3,899)	(5,699)
Deferred revenue	986	(977)
Customer deposits	(415)	720
Accrued income taxes and income taxes receivable	7,552	(1,120)
Other liabilities	836	(1,552)
NET CASH PROVIDED BY OPERATING ACTIVITIES	35,632	40,757
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant, and equipment	(3,811)	(5,743)
Purchases of marketable securities	(73,906)
Proceeds from maturities of marketable securities	15,826
Proceeds from sales of marketable securities	2,294
Proceeds from the sale of property, plant, and equipment	16	18
NET CASH USED IN INVESTING ACTIVITIES	(59,581)	(5,725)
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)
Shares repurchased for taxes for vested employee restricted stock grants	(1,061)	(1,039)
Excess tax benefit from share-based compensation		158
Dividends paid to shareholders	(2,497)	(2,501)
NET CASH USED IN FINANCING ACTIVITIES	(3,678)	(292)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	192	(447)
NET (DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(27,435)	34,293
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	129,298	118,697
CASH AND CASH EQUIVALENTS, END OF PERIOD	101,863	152,990
Supplemental disclosures of cash flow information:
Non-cash transfer of demonstration inventory to fixed asset	$ 1,669	$ 1,764