CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 74,052	$ 9,660	$ 3,155
Adjustments to reconcile net income to net cash provided by operating activities:
Amortization of deferred revenue	(5,880)	(5,284)	(3,275)
Depreciation	2,044	1,978	1,451
Amortization of intangibles	10,973	4,869	49
Amortization of premium and discount on investments, net	(458)	(778)	(775)
Stock-based employee compensation	6,077	4,263	4,373
Stock-based non-employee compensation	0	0	6
Non-cash expense under materials and license agreements	0	0	9
Stock-based compensation to Board of Directors and Scientific Advisory Board	809	781	1,377
Loss on stock warrant liability	0	0	4,190
Deferred Income Tax Expense (Benefit)	(41,418)	(11)	0
Retirement plan benefit expense	1,665	1,600	1,527
(Increase) decrease in assets:
Accounts receivable	(7,000)	2,070	(3,479)
Inventory	424	(7,175)	(3,841)
Other current assets	(2,706)	(2,284)	341
Other assets	35	33	(82)
Increase (decrease) in liabilities:
Accounts payable and accrued expenses	3,614	4,718	6,775
Other current liabilities	(11)	11	23
Deferred revenue	2,767	3,303	4,585
Net cash provided by operating activities	44,987	17,754	16,409
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(4,710)	(2,737)	(2,624)
Additions to intangibles	(359)	(109,102)	(440)
Purchases of investments	(362,838)	(304,500)	(337,442)
Proceeds from sale of investments	313,132	380,253	156,717
Net cash used in investing activities	(54,775)	(36,086)	(183,789)
CASH FLOWS FROM INVESTING ACTIVITIES:
Proceeds from issuance of common stock	343	321	249,936
Repurchase of common stock	(5,456)	(5,202)	0
Proceeds from the exercise of common stock options and warrants	2,832	1,483	13,343
Payment of withholding taxes related to stock-based employee compensation	(3,268)	(4,142)	(4,473)
Net cash (used in) provided by financing activities	(5,549)	(7,540)	258,806
(DECREASE) INCREASE IN CASH AND CASH EQUIVALENTS	(15,337)	(25,872)	91,426
CASH AND CASH EQUIVALENTS, BEGINNING OF YEAR	85,923	111,795	20,369
CASH AND CASH EQUIVALENTS, END OF YEAR	$ 70,586	$ 85,923	$ 111,795