Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013
OPERATING ACTIVITIES:
Net income	$ 22,527	$ 13,247
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	5,520	5,268
Compensation for stock options and restricted stock units	3,669	3,237
(Net recovery of) provision for bad debts	(272)	426
Deferred income tax (benefit) expense	(5,804)	996
Income tax benefit from exercise of stock options	(137)	(814)
Decrease (increase) in:
Accounts receivable	(5,392)	8,951
Inventories, net	(12,965)	620
Prepaid expenses and other current assets	(1,881)	(3,365)
(Decrease) increase in:
Accounts payable and accrued liabilities	(805)	(925)
Income taxes payable	(1,151)	(3,700)
Customer deposits	(1,659)	(258)
Unearned service revenues	2,827	512
Net cash provided by operating activities	4,477	24,195
INVESTING ACTIVITIES:
Purchases of property and equipment	(10,306)	(1,883)
Payments for intangible assets	(1,080)	(1,787)
Purchase of business acquired	(1,000)
Net cash used in investing activities	(12,386)	(3,670)
FINANCING ACTIVITIES:
Payments on capital leases	(6)	(76)
Income tax benefit from exercise of stock options	137	814
Proceeds from issuance of stock, net	2,522	3,267
Net cash provided by financing activities	2,653	4,005
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	(2,464)	(858)
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(7,720)	23,672
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	124,630	93,233
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 116,910	$ 116,905