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Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2015 | Dec. 31, 2014
--- | --- | ---
Assets: |  |
Cash and cash equivalents | $ 114,721 | $ 131,545
Money market funds | 251,046 | 26,046
Restricted cash | 0 | 300
Total Assets | 365,767 | 157,891
Quoted Prices in Active Markets for Identical Assets Level 1 [Member] |  |
Assets: |  |
Cash and cash equivalents | 114,721 | 131,545
Money market funds | 251,046 | 26,046
Restricted cash |  | 300
Total Assets | 365,767 | 157,891
Quoted Prices in Active Markets for Identical Assets Level 2 [Member] |  |
Assets: |  |
Cash and cash equivalents | 0 | 0
Money market funds | 0 | 0
Restricted cash |  | 0
Total Assets | 0 | 0
Quoted Prices in Active Markets for Identical Assets Level 3 [Member] |  |
Assets: |  |
Cash and cash equivalents | 0 | 0
Money market funds | 0 | 0
Restricted cash |  | 0
Total Assets | $ 0 | $ 0

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- Definition Fair value portion of a fund that invests in short-term money-market instruments, for example, but not limited to, commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and other highly liquid securities. + References No definition available. + Details
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- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + 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=36462937&loc=d3e19207-110258 + Details
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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 The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element. + References Reference 1: 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 + Details
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