Condensed Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2013	Oct. 31, 2012
CASH FLOWS FROM OPERATING ACTIVITIES:
Net (loss) income	$ (3,775)	$ 4,381
Adjustments to reconcile income from continuing operations to net cash provided by operating activities:
Provison for deferred income taxes	2,673	6,500
Depreciation and amortization	5,390	3,999
Share-based compensation expense	2,735	2,644
Excess tax benefit from share-based compensation	(3,064)	(1,853)
Write-down of inventory to net realizable value	300	861
Allowance for doubtful accounts	(7)	110
Contingent consideration		(25)
Loss on investment	484
Loss (gain) on sale of property, plant and equipment	13	(1)
Other		757
Net changes in operating assets and liabilities, exclusive of acquisition related assets and liabilities:
Accounts receivable	26,599	18,287
Inventory	(2,612)	(14,917)
Refundable income taxes	(8,520)	(5,870)
Other current assets	(606)	(1,317)
Accounts payable	397	(1,330)
Accrued liabilities	(9,733)	(12,037)
Deferred revenue	1,475	(3,849)
Accrued income taxes	(1,606)	(3,489)
Other liabilities	513	408
NET CASH FLOWS PROVIDED BY (USED IN) OPERATING ACTIVITIES	10,656	(6,741)
CASH FLOWS FROM INVESTING ACTIVITIES:
Additions to property, plant, and equipment	(4,163)	(5,628)
Acquisition of business, net of cash acquired	(10,561)
Proceeds from the sale of property, plant, and equipment	45	19
NET CASH FLOWS USED IN INVESTING ACTIVITIES	(14,679)	(5,609)
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	3,848	3,059
Shares repurchased for taxes for vested employee restricted stock grants	(6,085)	(3,784)
Excess tax benefit from share-based compensation	3,064	1,853
Repurchase of common stock	(3,731)	(3,937)
Dividends paid to shareholders	(1,243)	(1,443)
NET CASH FLOWS USED IN FINANCING ACTIVITIES	(4,147)	(4,252)
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	213	529
NET DECREASE IN CASH AND CASH EQUIVALENTS	(7,957)	(16,073)
CASH AND CASH EQUIVALENTS, BEGINNING OF THE PERIOD	113,033	187,011
CASH AND CASH EQUIVALENTS, END OF THE PERIOD	$ 105,076	$ 170,938