CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating activities:
Net loss	$ (31,280)	$ (1,672)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation	1,561	1,707
Amortization of patents	263	285
Amortization of licenses	471	569
Amortization of premium on investments, net	1,376	1,108
Amortization of debt issuance costs	135	100
Amortization of 2 3/4 percent convertible senior notes discount	1,671	1,543
Amortization of long-term financing liability for leased facility	1,652	1,637
Stock-based compensation expense	7,069	2,869
Gain on investments, net	(397)	(1,058)
Non-cash losses related to patents, licensing and property, plant and equipment	108	94
Tax benefit from other unrealized gains on securities	(2,276)	(64)
Changes in operating assets and liabilities:
Contracts receivable	1,279	(650)
Inventories	496	312
Other current and long-term assets	(896)	(1,601)
Accounts payable	(2,646)	(5,569)
Accrued compensation	(7,840)	(4,060)
Deferred rent	25	40
Accrued liabilities	2,643	2,355
Deferred contract revenue	(5,742)	(8,521)
Net cash used in operating activities	(32,328)	(10,576)
Investing activities:
Purchases of short-term investments	(69,185)	(64,552)
Proceeds from the sale of short-term investments	95,288	49,076
Purchases of property, plant and equipment	(1,403)	(222)
Acquisition of licenses and other assets, net	(333)	(702)
Proceeds from the sale of strategic investments	454	1,094
Net cash provided by (used in) investing activities	24,821	(15,306)
Financing activities:
Proceeds from equity awards	12,003	11,823
Principal payments on debt and capital lease obligations	(2,691)	(2,773)
Net cash provided by financing activities	9,312	9,050
Net increase (decrease) in cash and cash equivalents	1,805	(16,832)
Cash and cash equivalents at beginning of period	159,973	124,482
Cash and cash equivalents at end of period	161,778	107,650
Supplemental disclosures of cash flow information:
Interest paid	83	113
Income taxes paid	0	2
Supplemental disclosures of non-cash investing and financing activities:
Amounts accrued for capital and patent expenditures	$ 1,506	$ 715