CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net loss	$ (13,086)	$ (22,927)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	472	536
Gains on sales of fixed assets	(93)	0
Expenses for share-based compensation awards	2,609	1,495
Changes in assets and liabilities:
(Increase) decrease in accounts receivable	(887)	1,559
Decrease (increase) in other current assets	8	(467)
Decrease in other assets	0	1,050
Decrease in accounts payable and accrued expenses	(2,232)	(1,848)
Increase in other current liabilities	0	2
(Decrease) increase in deferred revenue - long term	(51)	60,000
(Decrease) increase in other liabilities	(534)	93
Net cash (used in) provided by operating activities	(13,794)	39,493
Cash flows from investing activities:
Capital expenditures	(518)	(29)
Proceeds from sales of fixed assets	124	0
Proceeds from redemption of auction rate securities	100	0
Net cash used in investing activities	(294)	(29)
Cash flows from financing activities:
Proceeds from the exercise of stock options and sale of common stock under the employee stock purchase plan	82	1,272
Net cash provided by financing activities	82	1,272
Net (decrease) increase in cash and cash equivalents	(14,006)	40,736
Cash and cash equivalents at beginning of period	70,105	47,918
Cash and cash equivalents at end of period	$ 56,099	$ 88,654

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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.