CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010
Cash flows from operating activities:
Net income (loss)	$ 21,127	$ (50,925)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	1,581	2,283
Expenses for share-based compensation awards	4,695	7,726
Changes in assets and liabilities:
(Increase) decrease in accounts receivable	(229)	3,045
Decrease (increase) in other current assets	986	(458)
Decrease in other assets	1,050	730
(Decrease) increase in accounts payable and accrued expenses	(2,802)	812
Increase in deferred revenue - current and long term	417	0
(Decrease) increase in other liabilities	(37)	1,718
Net cash provided by (used in) operating activities	26,788	(35,069)
Cash flows from investing activities:
Capital expenditures	(142)	(2,127)
Sales/maturities of marketable securities	200	1,700
Net cash provided by (used in) investing activities	58	(427)
Cash flows from financing activities:
Proceeds from the exercise of stock options and sale of common stock under the Employee Stock Purchase Plan	3,234	2,987
Net cash provided by financing activities	3,234	2,987
Net increase (decrease) in cash and cash equivalents	30,080	(32,509)
Cash and cash equivalents at beginning of period	47,918	90,903
Cash and cash equivalents at end of period	$ 77,998	$ 58,394

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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 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