Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash flows from operating activities:
Net income (loss)	$ 9,881	$ (10,975)	$ (19,319)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Depreciation and amortization	2,805	3,971	3,941
Stock-based compensation	1,526	1,433	1,565
Deferred income taxes	145	(450)	583
Other non-cash items	59	(156)	52
Changes in assets and liabilities:
Accounts receivable	(7,332)	(10,702)	9,837
Advance billings	(1,307)	(1,626)	3,351
Inventories	(7,519)	(5,317)	(2,503)
Prepaid expenses and other current assets	(4,878)	(536)	4,616
Other assets	34	85	252
Accounts payable	(3,979)	14,687	(5,312)
Accrued compensation and benefits and other current liabilities	4,149	(4,554)	(4,553)
Deferred revenue	(808)	1,830	(6,044)
Other liabilities	(434)	(526)	(2,434)
Net cash used in operating activities	(7,658)	(12,836)	(15,968)
Cash flows from investing activities:
(Increase) decrease in restricted cash	69	(202)	0
Purchases of property and equipment	(1,395)	(1,171)	(1,487)
Proceeds from sales of property and equipment	12	0	60
Net cash used in investing activities	(1,314)	(1,373)	(1,427)
Cash flows from financing activities:
Proceeds from revolving credit facility, net of borrowing costs	0	28,611	0
Repayment of revolving credit facility	(14,000)	(15,000)	0
Proceeds from issuance of common stock, net	32,213	576	366
Net cash provided by financing activities	18,213	14,187	366
Effect of exchange rate changes on cash and cash equivalents	(1,059)	246	310
Net increase (decrease) in cash and cash equivalents	8,182	224	(16,719)
Cash and cash equivalents, beginning of period	14,578	14,354	31,073
Cash and cash equivalents, end of period	22,760	14,578	14,354
Supplemental Disclosure:
Cash paid for interest	210	578	0
Cash paid for income taxes, net of refunds	$ 107	$ 422	$ 794