Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities
Net income	$ 1,868	$ 174
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	1,142	1,140
Deferred taxes	134us-gaap_DeferredIncomeTaxExpenseBenefit	312us-gaap_DeferredIncomeTaxExpenseBenefit
Stock-based compensation expense	1,126us-gaap_ShareBasedCompensation	1,172us-gaap_ShareBasedCompensation
Provision for excess inventory	242us-gaap_InventoryWriteDown	59us-gaap_InventoryWriteDown
Changes in operating assets & liabilities
Accounts receivable	(355)	(1,634)
Inventories	(6,963)us-gaap_IncreaseDecreaseInInventories	(52)us-gaap_IncreaseDecreaseInInventories
Prepaid expenses and other current assets	(1,085)	(1,252)
Accounts payable and other current liabilities	11,466	(2,025)
Deferred revenue	1,455	(614)
Income taxes	132	61
Other assets and liabilities	(422)	(1,304)
Net cash provided by (used in) operating activities	8,740	(3,963)
Cash flows used in investing activities
Expenditures for property, plant, and equipment	(320)	(227)
Net cash (used in) investing activities	(320)	(227)
Cash flows from financing activities
Decrease in restricted cash	758
Financing fees and other expenses	(847)us-gaap_PaymentsOfFinancingCosts
Principal payments on term loan	(14,530)us-gaap_RepaymentsOfLongTermDebt
Principal payments on sale leaseback obligation	(392)
Proceeds from sale leaseback obligation	48,940
Proceeds from exercise of stock options	937	1,277
Net cash provided by financing activities	34,866	1,277
Effect of exchange rate changes on cash	509	(338)
Net increase (decrease) in cash and cash equivalents	43,795	(3,251)
Cash and cash equivalents at beginning of period	30,753	46,290
Cash and cash equivalents at end of period	$ 74,548	$ 43,039

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