Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities:
Net income (loss)	$ (6,601)	$ 906
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization of property and equipment	7,532	6,045
Amortization of intangible assets	1,429	1,673
Unrealized foreign exchange differences	(101)	1,455
Amortization of debt discount and transaction costs	2,667	2,502
Stock-based compensation expense	9,007	7,557
Excess tax benefits from stock-based compensation expense	0	(53)
Other non-cash items	357	142
Changes in operating assets and liabilities:
Accounts receivable	(6,076)	(5,910)
Inventory, net	(1,693)	(8,160)
Prepaid expenses and other current assets	(7,459)	(2,299)
Other non-current assets	(68)	(197)
Accounts payable and other current and non-current liabilities	(1,408)	5,512
Accrued compensation	(8,904)	(8,776)
Deferred revenue	2,205	341
Net cash provided by (used in) operating activities	(9,113)	738
Cash flows from investing activities:
Capital expenditures	(22,741)	(9,989)
Cost of acquisitions, net	0	(3,000)
Proceeds from sale of equipment and an intangible asset	24	339
Proceeds from sales of marketable securities and investments	21,230	13,303
Proceeds from maturities of marketable securities and investments	58,627	61,774
Purchases of marketable securities and investments	(73,040)	(62,494)
Transfer from (to) restricted cash	(2,059)	31
Net cash used in investing activities	(17,959)	(36)
Cash flows from financing activities:
Net proceeds from the issuance of common shares and exercise of stock options	4,251	13,804
Excess tax benefits from stock-based compensation expense	0	53
Principal payment of notes payable	(43)	(39)
Net cash provided by financing activities	4,208	13,818
Effect of foreign exchange rate change on cash and cash equivalents	116	(1,557)
Net increase (decrease) in cash and cash equivalents	(22,748)	12,963
Cash and cash equivalents at beginning of period	112,568	96,663
Cash and cash equivalents at end of period	$ 89,820	$ 109,626