Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Operating activities:
Net loss	$ (116,389)	$ (83,132)	$ (53,901)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	5,108	3,519	1,707
Loss on disposal of property and equipment			46
Net amortization of premiums on marketable securities	1,685	2,494	1,882
Amortization of debt discount	1,179	144	109
Amortization of loan fees	350		13
Noncash interest income, net			(4)
Issuance of common stock in connection with professional services rendered	452		16
Warrant expense related to vesting of ADM Warrant (see Note 10)	98
Stock-based compensation expense	18,653	15,356	10,907
Loss from equity method investments	8,237	1,824
Revaluation of warrant liability	(147)	(2,284)	3,637
Revaluation of derivative liability	6,392
Changes in operating assets and liabilities:
Accounts receivable	(7,268)	749	(3,359)
Unbilled revenue	2,045	739	(422)
Inventories	(2,946)	(3,762)	(3,129)
Prepaid expenses and other current assets	(764)	611	(2,298)
Other assets	3,262	2	69
Accounts payable	(2,563)	(1,396)	3,025
Accrued liabilities	5,955	9	5,183
Deferred revenue	1,983	(2,722)	1,651
Other current and long-term liabilities	(112)	278	(37)
Net cash used in operating activities	(74,790)	(67,571)	(34,905)
Investing activities:
Purchases of property, plant and equipment	(10,217)	(12,554)	(15,502)
Proceeds received from the sale of equipment			290
Purchases of marketable securities	(133,601)	(64,908)	(240,298)
Maturities of marketable securities	126,073	130,682	58,866
Proceeds from sales of marketable securities	10,890	29,014	13,863
Capital contributions in unconsolidated joint ventures	(12,431)	(10,000)
Capitalized interest related to unconsolidated joint venture	(1,055)
Restricted cash			(50)
Net cash (used in) provided by investing activities	(20,341)	72,234	(182,831)
Financing activities:
Repayments under loan agreements	(14,917)	(5,408)	(333)
Proceeds from the issuance of senior subordinated convertible notes, net of discount	119,750
Payment for equity financing costs			(3,868)
Proceeds from the issuance of common stock, net of repurchases	3,714	1,737	866
Proceeds from issuance of common stock, pursuant to ESPP	1,039	1,161
Early exercise of stock options subject to repurchase	(35)	(60)	(105)
Payments received on promissory notes to stockholders			1,601
Proceeds from borrowings under loan agreements	10,369		15,000
Payment for loan costs and fees	(541)		(90)
Proceeds from exercise of common and preferred stock warrants			37
Proceeds from issuance of common stock in initial public offering, net of underwriting discounts and commission			201,236
Net cash provided by (used in) financing activities	119,379	(2,570)	214,344
Effect of exchange rate changes on cash and cash equivalents	(89)	(55)	(325)
Net increase (decrease) of cash and cash equivalents	24,159	2,038	(3,717)
Cash and cash equivalents-beginning of period	30,818	28,780	32,497
Cash and cash equivalents-end of period	54,977	30,818	28,780
Supplemental disclosures of cash flow information:
Interest paid in cash	3,499	409	452
Income taxes paid in cash
Supplemental disclosure of noncash investing and financing activities:
Accretion of redeemable convertible preferred stock			60
Capital assets in accounts payable and accrued liabilities	3,413	421	3,103
Accrued offering costs			428
Debt issue costs in accounts payable and accrued liabilities		148
Addition of land, building and equipment under notes payable			5,248
Change in unrealized gain (loss) on marketable securities	(240)	642	(276)
Foreign currency translation adjustment related to unconsolidated joint venture	(2,478)
Conversion of convertible preferred stock to common stock upon initial public offering			128,374
Reclassification of warrant liability to additional paid-in capital		4,586	6,598
Reclassification of deferred offering costs to additional paid-in capital upon initial public offering			4,295
Warrant issued for investment in unconsolidated joint venture		10,361
Capital contribution to unconsolidated joint venture settled with reduction of receivable from unconsolidated joint venture		511
Common stock issue in lieu of cash bonus	121
Common stock issued in connection with use and operation of the Clinton Facility (see Note 10)	7,125
Conversion of Senior Convertible Notes to common stock	40,616
Early conversion payment on Senior Convertible Notes settled in common stock	$ 3,602