Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
OPERATING ACTIVITIES:
Net income	$ 34,480	$ 31,121	$ 43,071
Adjustments to reconcile net income to net cash provided by operating activities:
(Benefit from) provision for deferred income taxes	(5,412)	1,006	(3,050)
Depreciation and amortization	22,057	17,275	17,775
Change in fair value of contingent consideration	125	(25)	120
Share-based compensation expense	11,512	11,601	13,396
Excess tax benefit from share-based compensation	(3,982)	(2,053)	(184)
Other		1,188
Write-down of inventory to net realizable value	3,918	4,726	2,441
Allowance for doubtful accounts	203	345	200
Loss (gain) on investment	484		(2,500)
Loss (gain) on disposal of property, plant and equipment	17	(58)	(14)
Net changes in operating assets and liabilities, exclusive of acquisition related assets and liabilities:
Accounts receivable	6,633	(10,523)	(8,258)
Inventory	(12,347)	(2,127)	(7,206)
Refundable income taxes	(5,594)	42	312
Other current assets	2,525	(123)	2,525
Accounts payable	3,222	(11,991)	1,548
Accrued liabilities	(9,100)	(305)	3,948
Customer deposits	(213)	440	903
Deferred revenue	1,533	(2,885)	4,170
Accrued income taxes	(3,175)	854	3,850
Other liabilities	1,045	2,935	663
NET CASH PROVIDED BY OPERATING ACTIVITIES	47,931	41,443	73,710
INVESTING ACTIVITIES:
Additions to property, plant, and equipment	(17,517)	(25,551)	(30,606)
Purchases of marketable securities in Rabbi Trust under the Non Qualified Deferred Compensation Plan	(715)
Acquisition of business, net of cash acquired	(10,561)	(79,273)
Proceeds from the sale of other investments			2,500
Proceeds from the sale of property, plant, and equipment and other assets	260	146	207
NET CASH USED FOR INVESTING ACTIVITIES	(28,533)	(104,678)	(27,899)
FINANCING ACTIVITIES:
Issuance of stock pursuant to exercise of stock options, employee stock purchase plan, restricted stock plans, and non-employee director stock plan	5,379	4,684	2,000
Shares repurchased for taxes for vested employee restricted stock grants	(7,680)	(4,661)	(471)
Repayments of other credit facilities		(3,014)
Borrowing of other credit facilities		2,230
Contingent consideration payment		(340)
Excess tax benefit from share-based compensation	3,982	2,053	184
Repurchase of common stock	(14,959)	(7,945)	(23,260)
Dividends paid to shareholders	(4,962)	(5,114)	(4,980)
NET CASH USED FOR FINANCING ACTIVITIES	(18,240)	(12,107)	(26,527)
EFFECT OF EXCHANGE RATE CHANGES ON CASH	349	1,364	(1,929)
NET INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	1,507	(73,978)	17,355
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	113,033	187,011	169,656
CASH AND CASH EQUIVALENTS, END OF YEAR	114,540	113,033	187,011
Supplemental disclosures of cash flow information:
Income taxes paid, net of refunds	8,024	11,339	(935)
Fixed asset additions in accounts payable and accrued liabilities	$ 705	$ 1,620	$ 1,755