CONDENSED STATEMENTS OF CASH FLOWS (USD $) In Thousands	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010
Operating Activities
Net income (loss)	$ 93,138	$ 297
Adjustments to reconcile net income (loss) to net cash (used in) provided by operating activities:
Depreciation and amortization	123	210
Loss on disposal of property and equipment	0	46
Stock-based compensation	1,867	1,061
Changes in assets and liabilities:
Accounts receivable	(1,597)	473
Inventories	(3,443)	1,089
Prepaid and other assets	(1,572)	(381)
Accounts payable and other accrued liabilities	4,074	(58)
Accrued compensation	729	(985)
Deferred revenue	(11,235)	(5,395)
Net cash provided by (used in) operating activities	82,084	(3,643)
Investing Activities
Purchases of property and equipment	(444)	(58)
Purchases of marketable securities	(94,777)	(38,579)
Maturities of marketable securities	21,399	34,490
Sales of marketable securities	0	4,482
Net cash provided by (used in) investing activities	(73,822)	335
Financing Activities
Principal payments on long-term debt	(2,098)	(1,867)
Proceeds from issuance of common stock	7,621	599
Net cash provided by (used in) financing activities	5,523	(1,268)
Net increase (decrease) in cash and cash equivalents	13,785	(4,576)
Cash and cash equivalents at beginning of period	22,526	26,821
Cash and cash equivalents at end of period	$ 36,311	$ 22,245

Name:	us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract
Namespace Prefix:	us-gaap
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

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 should not be reported as cash and cash equivalents.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7, 26

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 8, 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 95
-Paragraph 7
-Footnote 1

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Paragraph 1
-Article 5