v2.4.0.8

Fair Value Measurements (Details) (USD $) In Thousands, unless otherwise specified | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2014 | Mar. 31, 2013 | Dec. 31, 2013
Change in the fair value of Series D Warrants |  |  |
Change in fair value of warrant liability | $ 688 | $ (8) | $ (33)
Recurring basis | Total |  |  |
Assets: |  |  |
Cash equivalents | 2,438 |  | 3,357
Liabilities: |  |  |
Series D redeemable convertible preferred stock warrants | 814 |  | 126
Change in the fair value of Series D Warrants |  |  |
Balance at the end of the period | 814 |  | 126
Recurring basis | Level 1 |  |  |
Assets: |  |  |
Cash equivalents | 2,438 |  | 3,357
Recurring basis | Level 3 |  |  |
Liabilities: |  |  |
Series D redeemable convertible preferred stock warrants | 814 |  |
Change in the fair value of Series D Warrants |  |  |
Balance at the beginning of the period | 126 |  |
Change in fair value of warrant liability | 688 |  |
Balance at the end of the period | $ 814 |  |

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- Definition Fair value portion 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. + 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 + Details
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- Definition Amount of expense (income) related to adjustment to fair value of warrant liability. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section 25 -Paragraph 13 -URI http://asc.fasb.org/extlink&oid=6939902&loc=d3e20148-110875 + Details
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- Definition Fair value portion of warrants not settleable in cash classified as equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258 + Details
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