CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Operating activities:
Net loss	$ (43,361)	$ (11,798)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Depreciation	3,141	3,375
Amortization of patents	543	584
Amortization of licenses	941	1,051
Amortization of premium on investments, net	3,847	2,382
Amortization of debt issuance costs	272	202
Amortization of 2 3/4 percent convertible senior notes discount	3,366	3,109
Amortization of long-term financing liability for leased facility	3,306	3,276
Stock-based compensation expense	14,776	5,505
Gain on investments, net	(137)	(1,898)
Non-cash losses related to patents, licensing and property, plant and equipment	325	263
Tax benefit from other unrealized gains on securities	(1,395)	0
Changes in operating assets and liabilities:
Contracts receivable	(30,839)	(1,502)
Inventories	257	(2,188)
Other current and long-term assets	(694)	(492)
Accounts payable	1,991	(1,833)
Accrued compensation	(5,738)	(847)
Deferred rent	69	98
Accrued liabilities	1,965	(135)
Deferred contract revenue	(18,978)	13,012
Net cash (used in) provided by operating activities	(66,343)	12,164
Investing activities:
Purchases of short-term investments	(179,196)	(144,250)
Proceeds from the sale of short-term investments	175,777	96,926
Purchases of property, plant and equipment	(3,100)	(591)
Acquisition of licenses and other assets, net	(1,791)	(1,171)
Proceeds from the sale of strategic investments	737	1,938
Net cash used in investing activities	(7,573)	(47,148)
Financing activities:
Proceeds from equity awards	13,416	36,879
Net proceeds from public common stock offering	0	173,223
Proceeds from equipment financing arrangement	0	2,513
Principal payments on debt and capital lease obligations	(5,392)	(5,573)
Net cash provided by financing activities	8,024	207,042
Net (decrease) increase in cash and cash equivalents	(65,892)	172,058
Cash and cash equivalents at beginning of period	159,973	124,482
Cash and cash equivalents at end of period	94,081	296,540
Supplemental disclosures of cash flow information:
Interest paid	2,920	2,977
Income taxes paid	0	2
Supplemental disclosures of non-cash investing and financing activities:
Amounts accrued for capital and patent expenditures	$ 453	$ 1,055