CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 26, 2015
OPERATING ACTIVITIES:
Net income	$ 7,562	$ 3,928
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	9,733	8,022
Compensation for stock options and restricted stock units	4,068	3,791
Provision for bad debts	727	462
Loss on disposal of assets	814	877
Write-down of inventories	2,937	9,560
Deferred income tax (benefit) expense	(734)	556
Income tax benefit from exercise of stock options	(354)	(292)
Decrease (increase) in:
Accounts receivable	12,850	17,205
Inventories	(8,689)	(21,693)
Prepaid expenses and other current assets	(995)	(5,740)
(Decrease) increase in:
Accounts payable and accrued liabilities	1,128	(8,779)
Customer deposits	(1,155)	(473)
Unearned service revenues	559	467
Net cash provided by operating activities	28,451	7,891
INVESTING ACTIVITIES:
Proceeds from sale of investments	11,000	0
Purchases of property and equipment	(5,272)	(8,462)
Payments for intangible assets	(1,440)	(1,751)
Acquisition of business, net of cash received	(20,911)	(12,066)
Net cash used in investing activities	(16,623)	(22,279)
FINANCING ACTIVITIES:
Payments on capital leases	(6)	(6)
Payment of contingent consideration for acquisitions	(434)	0
Income tax benefit from exercise of stock options	354	292
Proceeds from issuance of stock, net	519	2,286
Net cash provided by financing activities	433	2,572
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	1,732	(1,498)
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS	13,993	(13,314)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	107,356	109,289
CASH AND CASH EQUIVALENTS, END OF PERIOD	$ 121,349	$ 95,975