| **Fair Value Measurements**                  | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       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| **Notes to Financial Statements [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               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| Fair Value Measurements                      | 4.  Fair Value Measurements and Marketable SecuritiesOur available-for-sale investments consist of money market funds and auction rate securities and are recorded at fair value in the accompanying Consolidated Balance Sheets in accordance with ASC 320 Investments - Debt and Equity Securities. The change in the fair value of these investments is recorded as a component of other comprehensive loss (see Note 2. Summary of Significant Accounting Policies - Fair Value Measurements in the notes to consolidated financial statements included in our 2010 Annual Report on Form 10-K).The following tables present our available-for-sale investments measured at fair value on a recurring basis, summarized by valuation hierarchy, as of September 30, 2011 and December 31, 2010:      Fair Value Measurements at September 30, 2011    Balance atSeptember 30, 2011  Quoted Prices in Active Markets for Identical Assets (Level 1)  Significant Other Observable Inputs (Level 2)  Significant Unobservable Inputs (Level 3)               Money market funds $70,954  $70,954  $-  $- Auction rate securities  3,424   -   -   3,424 Total $74,378  $70,954  $-  $3,424       Fair Value Measurements at December 31, 2010    Balance atDecember 31, 2010  Quoted Prices in Active Markets for Identical Assets (Level 1)  Significant Other Observable Inputs (Level 2)  Significant Unobservable Inputs (Level 3)               Money market funds $43,958  $43,958  $-  $- Auction rate securities  3,608   -   -   3,608 Total $47,566  $43,958  $-  $3,608 At September 30, 2011 we hold $3.4 million (4.6% of total assets measured at fair value) in auction rate securities which are classified as Level 3. The fair value of these securities includes $2.5 million of U.S. government subsidized securities collateralized by student loan obligations and $0.9 million of investment company perpetual preferred stock. We will not realize cash in respect of the principal amount of these securities until the issuer calls or restructures the security, the security reaches any scheduled maturity and is paid, or a buyer outside the auction process emerges. As of September 30, 2011, we have received all scheduled interest payments on these securities, which, in the event of auction failure, are reset according to contractual terms in the governing instruments.The valuation of auction rate securities we hold is based on Level 3 unobservable inputs, which consist of our internal analysis of (i) timing of expected future successful auctions, (ii) collateralization of underlying assets of the security, and (iii) credit quality of the security. In re-evaluating the valuation of these securities as of September 30, 2011, the temporary impairment amount decreased to $276 at September 30, 2011 from $292 at December 31, 2010. Due to the uncertainty related to the liquidity in the auction rate security market and therefore when individual positions may be liquidated, we have classified these auction rate securities as long-term assets on our accompanying Consolidated Balance Sheets. We continue to monitor markets for our investments and consider the impact, if any, of market conditions on the fair market value of our investments. We do not believe the carrying values of our investments are other than temporarily impaired and therefore expect the positions will eventually be liquidated without significant loss.For those of our financial instruments with significant Level 3 inputs (all auction rate securities), the following table summarizes the activities for the three and nine months ended September 30, 2011 and 2010:      Fair Value Measurements Using SignificantUnobservable Inputs(Level 3)For the Three Months Ended September 30,  Description    2011      2010                    Balance at beginning of period  $   3,516    $     3,608  Transfers into Level 3                  -                       -  Total realized/unrealized gains (losses)                Included in net loss                  -                       -  Included in comprehensive loss (1)                  8                      -  Settlements       (100))        -  Balance at end of period  $  3,424    $     3,608  (1) Total amount of unrealized gains (losses) for the period included in other comprehensive loss attributable to the change in fair market value of related assets still held at the reporting date  $               -    $                 -        Fair Value Measurements Using SignificantUnobservable Inputs(Level 3)For the Nine Months Ended September 30,  Description    2011      2010                    Balance at beginning of period  $   3,608    $    3,792  Transfers into Level 3                  -                        -  Total realized/unrealized gains (losses)                Included in net loss                  -                        -  Included in comprehensive loss (1)                16              16  Settlements            (200)         (200)  Balance at end of period  $   3,424    $            3,608  (1) Total amount of unrealized gains (losses) for the period included in other comprehensive loss attributable to the change in fair market value of related assets still held at the reporting date  $      -    $                -  |

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| - Definition
This item represents the complete disclosure regarding the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the Company is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risk is are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15B -Subparagraph a, bReference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 3, 10, 14, 15Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 133 -Paragraph 44A, 44BReference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32, 33, 34Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15C, 15DReference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 15A -Subparagraph a-dReference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 159 -Paragraph 17-22, 27, 28
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