Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities:
Net income (loss)	$ (6,956)	$ (7,419)
Adjustments to reconcile to net cash provided by (used in) operating activities:
Stock-based compensation expense	9,945	7,790
Depreciation and amortization	17,770	17,298
Income taxes	547	630
Change in fair value of contingent obligations	935	751
Impairment of long-lived assets	1,114	0
Excess tax benefits from stock-based compensation	(10,442)	(7,241)
Other	775	153
Changes in operating assets and liabilities:
Accounts receivable	53,933	(40,884)
Inventories	(19,738)	(19,034)
Income taxes	(14,556)	(16,740)
Prepaid expenses and other assets	(1,713)	2,465
Accounts payable	11,287	2,062
Accrued expenses and other liabilities	(3,533)	157
Accrued compensation	(4,966)	(5,473)
Provision for chargebacks	274	(253)
Deferred revenue	1,007	2,368
Net cash provided by (used in) operating activities	35,683	(63,370)
Cash flows from investing activities:
Purchases of property, plant and equipment	(39,246)	(19,681)
Net cash used in investing activities	(39,246)	(19,681)
Cash flows from financing activities:
Proceeds from other long-term debt obligations	0	2,000
Issuance of common stock upon exercise of stock options	14,524	13,162
Excess tax benefits from stock-based compensation	10,442	7,241
Contingent obligation payments	(971)	(5,002)
Net cash provided by financing activities	23,995	17,401
Effect of exchange rate changes on cash and cash equivalents	168	(8)
Net increase (decrease) in cash and cash equivalents	20,600	(65,658)
Cash and cash equivalents at beginning of period	312,795	280,499
Cash and cash equivalents at end of period	$ 333,395	$ 214,841