CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows from operating activities:
Net loss from continuing operations	$ (139,733)	$ (47,026)	$ (75,434)
Adjustments to reconcile net loss from continuing operations to net cash used for operating activities from continuing operations:
Provision for cash discounts	53
Depreciation	271	102	138
Amortization of discount or premium on available-for-sale securities	3,958	3,118	1,655
Net realized gain on investments	(8)		(5)
Share-based compensation expense	15,938	7,353	6,443
Loss on early extinguishment of debt			5,958
Changes in assets and liabilities:
Accounts receivable	(2,835)
Inventories	(22,050)	118	(3,225)
Prepaid expenses and other assets	(17,653)	(145)	2,658
Accounts payable	22,202	545	(5,687)
Accrued and other liabilities	7,385	15	1,197
Deferred revenue	1,154
Net cash used for operating activities from continuing operations	(131,318)	(35,920)	(66,302)
Net cash (used for) provided by operating activities from discontinued operations	(885)	(980)	2,195
Net cash used for operating activities	(132,203)	(36,900)	(64,107)
Cash flows from investing activities:
Property and equipment purchases	(1,669)	(201)	(105)
Release of restricted cash			700
Purchases of available-for-sale securities	(226,654)	(137,409)	(209,759)
Proceeds from maturity of available-for-sale securities	133,250	129,000	243,900
Proceeds from sale of available-for-sale securities	40,763		28,487
Net cash (used for) provided by investing activities from continuing operations	(54,310)	(8,610)	63,223
Net cash provided by investing activities from discontinued operations			21,546
Net cash (used for) provided by investing activities	(54,310)	(8,610)	84,769
Cash flows from financing activities:
Payments of notes payable			(23,000)
Net proceeds from exercise of common stock options	13,250	2,354	3,617
Sale of common stock through employee stock purchase plan	314	211	304
Net proceeds from issuance of common stock	192,000	45,283
Net cash provided by (used for) financing activities from continuing operations	205,564	47,848	(19,079)
Net cash used for financing activities from discontinued operations			(4,900)
Net cash provided by (used for) financing activities	205,564	47,848	(23,979)
Net increase (decrease) in cash and cash equivalents	19,051	2,338	(3,317)
Cash and cash equivalents:
Beginning of year	39,554	37,216	40,533
End of year	58,605	39,554	37,216
Supplemental cash flow disclosure:
Interest paid			6,030
Income taxes paid	7	24	41
Non-cash investing and financing activities:
Unrealized gain on securities	$ 8	$ 21	$ 7

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Includes currency on hand as well as demand deposits with banks or financial institutions. It also includes other kinds of accounts that have the general characteristics of demand deposits in that the Entity may deposit additional funds at any time and also effectively may withdraw funds at any time without prior notice or penalty. Cash equivalents, excluding items classified as marketable securities, include short-term, highly liquid investments that are both readily convertible to known amounts of cash, and so near their maturity that they present minimal risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three years ago does not become a cash equivalent when its remaining maturity is three months. Compensating balance arrangements that do not legally restrict the withdrawal or usage of cash amounts may be reported as Cash and Cash Equivalents, while legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or company statements of intention with regard to particular deposits are not generally reported as cash and cash equivalents. Includes cash and cash equivalents associated with the entity's continuing operations. Excludes cash and cash equivalents associated with the disposal group (and discontinued operation).