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 loss	$ (39,674)	$ (43,413)	$ (89,266)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	7,408	8,949	12,337
Loss on goodwill and purchased intangible assets impairment	0	0	49,521
Impairment loss on equipment, leasehold improvements and software license intangible assets	0	418	100
Provision for bad debts, net of recoveries	86	1,936	439
Net impairment loss on marketable securities	0	0	39
Provision for excess and obsolete inventory	3,382	4,344	2,843
Share-based compensation expense	3,588	3,443	7,500
Change in fair value of warrant liability and fair value of beneficial conversion feature on convertible Series C preferred shares	3,725	0	0
Shareholder litigation loss	0	14,326	0
Non-cash income tax expense	87	220	462
Changes in assets and liabilities:
Accounts receivable	15,688	730	(6,242)
Inventories	(13,392)	6,879	420
Prepaid expenses and other assets	(2,403)	(489)	(1,237)
Accounts payable	10,036	(19,237)	(10,433)
Accrued expenses, income taxes, and other	(4,798)	(4,733)	3,638
Net cash used in operating activities	(16,267)	(26,627)	(29,879)
Cash flows from investing activities:
Purchases of property and equipment	(1,753)	(5,011)	(4,579)
Purchases of intangible assets	(431)	0	(104)
Purchases of marketable securities	(1,359)	(24,262)	(44,216)
Marketable securities maturities / sales	23,975	40,897	46,696
Net cash provided by (used in) investing activities	20,432	11,624	(2,203)
Cash flows from financing activities:
Proceeds from the issuances of Series C preferred and common stock, net of issuance costs	14,163	0	0
Proceeds from the issuance of short-term debt, net of issuance costs	0	20,300	14,000
Principal repayments of short-term debt	(2,566)	(17,734)	(14,000)
Repayment of litigation settlement note payable, including interest	(5,026)	0	0
Borrowings on revolving credit facility	5,158	0	0
Principal payments under capital lease obligations	0	0	(46)
Taxes paid on vested restricted stock units net of proceeds from stock option exercises and ESPP	(821)	(552)	1,166
Net cash provided by financing activities	10,908	2,014	1,120
Effect of exchange rates on cash and cash equivalents	(131)	(144)	(63)
Net increase (decrease) in cash and cash equivalents	14,942	(13,133)	(31,025)
Cash and cash equivalents, beginning of period	2,911	16,044	47,069
Cash and cash equivalents, end of period	17,853	2,911	16,044
Cash paid during the year for:
Interest	119	65	17
Income taxes	108	121	104
Supplemental disclosures of non-cash activities:
Building rent incentives to fund leasehold improvements	0	359	0
Issuance of common stock for litigation settlement	5,000	0	0
Initial fair value of warrant liability recorded upon issuance of Series C preferred and common stock	4,939	0	0
Issuance of common stock for conversion of Series C preferred shares	$ 940	$ 0	$ 0