| **CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)In Thousands**                                   | 9 Months Ended |
|-------------------------------------------------------------------------------------------------------------|----------------|
||
| **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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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
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
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The net change between the beginning and ending balance of cash and cash equivalents.
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| - Definition
The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.
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| - Definition
The net change during the reporting period in the aggregate amount of obligations and expenses incurred but not paid.
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| - Definition
The net change during the reporting period in amount due within one year (or one business cycle) from customers for the credit sale of goods and services.
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| - Definition
The net change during the reporting period, excluding the portion taken into income, in the liability reflecting services yet to be performed by the reporting entity for which cash or other forms of consideration was received or recorded as a receivable.
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| - Definition
The net change during the reporting period in other expenses incurred but not yet paid. This element should be used when there is no other more specific or appropriate element.
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| - Definition
The net change during the reporting period in other operating assets not otherwise defined in the taxonomy.
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| - Definition
The net change during the reporting period in the value of this group of assets within the working capital section.
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| - Definition
The net cash inflow (outflow) from financing activity for the period.
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| - Definition
The net cash inflow (outflow) from investing activity.
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| - Definition
The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities generally involve producing and delivering goods and providing services. Operating activity cash flows include transactions, adjustments, and changes in value that are not defined as investing or financing activities.
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| - Definition
The net cash from (used in) all of the entity's operating activities, including those of discontinued operations, of the reporting entity. Operating activities include all transactions and events that are not defined as investing or financing activities. Operating activities generally involve producing and delivering goods and providing services. Cash flows from operating activities are generally the cash effects of transactions and other events that enter into the determination of net income.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The portion of consolidated profit or loss for the period, net of income taxes, which is attributable to the parent. If the entity does not present consolidated financial statements, the amount of profit or loss for the period, net of income taxes.
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| - Definition
The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total cash inflow associated with the amount received from holders to acquire the entity's shares under incentive and share awards, including stock option exercises.
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| - Definition
The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (trading, held-to-maturity, or available-for-sale) during the period.
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| - Definition
The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock options, amortization of restricted stock, and adjustment for officers compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.
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