Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Cash flows from operating activities
Net loss	$ (8,348)us-gaap_NetIncomeLoss	$ (10,894)us-gaap_NetIncomeLoss
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation and amortization	3,317us-gaap_DepreciationAndAmortization	3,507us-gaap_DepreciationAndAmortization
Stock-based compensation	334us-gaap_ShareBasedCompensation	448us-gaap_ShareBasedCompensation
Deferred taxes	29us-gaap_DeferredIncomeTaxExpenseBenefit
Changes in operating assets and liabilities:
Accounts receivable	770	(4,597)
Inventories	647us-gaap_IncreaseDecreaseInInventories	5,781us-gaap_IncreaseDecreaseInInventories
Other inventory supplies	100	(140)
Prepaid expenses and other assets	332	(354)
Accounts payable	(1,050)	1,192
Accrued payroll	(258)	(56)
Corporate income and franchise taxes	(189)	(92)
Advanced payments	(4)	347
Accrued and other current liabilities	313	385
Net cash used in operating activities	(4,007)	(4,473)
Cash flows from investing activities
Purchases of property and equipment	(234)	(1,924)
Purchases of investments	(307)us-gaap_PaymentsToAcquireInvestments	(26,675)us-gaap_PaymentsToAcquireInvestments
Proceeds from sale of investments	5,000	4,500
Net cash provided by (used in) investing activities	4,459	(24,099)
Cash flows from financing activities
Proceeds from issuance of common stock, net of issuance costs		34,961
Proceeds from exercise of options		256
Taxes paid related to net share settlement of equity awards	(8)
Restricted cash	4	4
Net cash (used in) provided by financing activities	(4)	35,221
Net effect of currency translation	326	(39)
Net increase in cash and cash equivalents	774	6,610
Cash and cash equivalents, beginning of period	24,353	21,071
Cash and cash equivalents, end of period	$ 25,127	$ 27,681

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The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of increase (decrease) from the effect of exchange rate changes on cash and cash equivalent balances held in foreign currencies.

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The increase (decrease) during the reporting period in the aggregate amount of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business.

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The increase (decrease) during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.

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The increase (decrease) during the period in accrued salaries.

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The increase (decrease) during the period in the carrying amount of capitalized costs of materials, supplies, or both, which are not included in inventory.

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The increase (decrease) during the reporting period in the value of prepaid expenses and other assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes.

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The net cash inflow or outflow for the increase (decrease) associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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The net cash paid (received) associated with the acquisition or disposal of all investments, including securities and other assets.

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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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The cash inflow from the additional capital contribution to the entity.

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