v2.4.0.8

Cash and Cash Equivalents, Short-term Investments and Fair Value of Financial Instruments marketable securities - gain or loss (Details) (USD $) | 9 Months Ended |  |  |
--- | --- | --- | --- | ---
Sep. 30, 2013 | Dec. 31, 2012 | Sep. 30, 2012 | Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Money Market Fund - daily traded value | $ 1.00 |  |  |
Cash and cash equivalents, Amortized Cost | 116,190,000 | 62,313,000 | 54,818,000 | 191,762,000
Cash, cash equiv and S-T-I: Amortized cost | 116,190,000 | 62,314,000 |  |
Cash, cash equiv and S-T-I: Gross unrealized gains | 0 | 0 |  |
Cash, cash equiv and S-T-I: Gross unrealized losses | 0 | 1,000 |  |
Cash, Cash Equivalents, and Short-term Investments | 116,190,000 | 62,313,000 |  |
Cash [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Cash and cash equivalents, Amortized Cost | 51,415,000 | 23,422,000 |  |
Cash and cash equivalents - gross unrealized gain | 0 | 0 |  |
Cash and cash equivalents - Gross unrealized losses | 0 | 0 |  |
Cash and Cash Equivalents, Fair Value Disclosure | 51,415,000 | 23,422,000 |  |
Money Market Funds [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Cash and cash equivalents, Amortized Cost | 64,775,000 | 38,892,000 |  |
Cash and cash equivalents - gross unrealized gain | 0 | 0 |  |
Cash and cash equivalents - Gross unrealized losses | 0 | 1,000 |  |
Cash and Cash Equivalents, Fair Value Disclosure |  | 38,891,000 |  |
Cash and Cash Equivalents [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Cash, Cash Equivalents, and Short-term Investments | 116,190,000 | 62,313,000 |  |
Cash and Cash Equivalents [Member] | Cash [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Cash and Cash Equivalents, Fair Value Disclosure | 51,415,000 | 23,422,000 |  |
Cash and Cash Equivalents [Member] | Money Market Funds [Member] |  |  |  |
Schedule of Available-for-sale Securities [Line Items] |  |  |  |
Cash and Cash Equivalents, Fair Value Disclosure | $ 64,775,000 | $ 38,891,000 |  |

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- Definition Cash, cash equivalents and short-term investments-Amortized cost + References No definition available. + Details
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- Definition Money Market Fund - daily traded value = $1.00 per share + References No definition available. + Details
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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8, 9 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6361293&loc=d3e6676-107765 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3044-108585 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 26 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item 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 Company 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7 -Footnote 1 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 8 -Footnote 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 95 -Paragraph 7, 8, 9, 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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