CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Operating activities:
Net (loss) income	$ (3,458)	$ 7,562
Adjustments to reconcile net (loss) income to net cash (used in) provided by operating activities:
Depreciation and amortization	12,075	9,733
Stock-based compensation	4,823	4,068
Provision for bad debts	321	727
Loss on disposal of assets	263	814
Provision for excess and obsolete inventory	1,271	2,937
Deferred income tax expense (benefit)	224	(734)
Income tax benefit from exercise of stock options	0	(354)
Decrease (increase) in:
Accounts receivable	3,701	12,850
Inventories	(11,450)	(8,689)
Prepaid expenses and other current assets	(3,834)	(995)
(Decrease) increase in:
Accounts payable and accrued liabilities	(2,774)	1,128
Income taxes payable	(598)	0
Customer deposits	(6)	(1,155)
Unearned service revenues	(1,326)	559
Net cash (used in) provided by operating activities	(768)	28,451
Investing activities:
Proceeds from sale of investments	32,000	11,000
Purchases of property and equipment	(6,081)	(5,272)
Payments for intangible assets	(1,345)	(1,440)
Acquisition of business	(5,496)	(20,911)
Net cash provided by (used in) investing activities	19,078	(16,623)
Financing activities:
Payments on capital leases	(6)	(6)
Payment of contingent consideration for acquisitions	(521)	(434)
Income tax benefit from exercise of stock options	0	354
Proceeds from issuance of stock	387	519
Net cash (used in) provided by financing activities	(140)	433
Effect of exchange rate changes on cash and cash equivalents	5,502	1,732
Increase in cash and cash equivalents	23,672	13,993
Cash and cash equivalents, beginning of period	106,169	107,356
Cash and cash equivalents, end of period	$ 129,841	$ 121,349