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FINANCIAL INSTRUMENTS AND FAIR VALUE MEASUREMENTS (Details) (USD $) | Mar. 31, 2014 | Dec. 31, 2013
--- | --- | ---
Fair value disclosure |  |
Short-term investments | $ 35,960,000 | $ 35,906,000
Restricted cash, cash equivalents, and short-term investments | 1,903,000 | 1,902,000
Concentrations of Credit Risk of Financial Instruments |  |
Cash, cash equivalents, and certificates of deposit which are not FDIC-insured | 49,400,000 | 49,400,000
Fair value disclosure |  |
Fair value disclosure |  |
Cash and cash equivalents | 95,728,000 | 105,354,000
Fair value disclosure | Cash deposits |  |
Fair value disclosure |  |
Cash and cash equivalents | 54,880,000 | 63,547,000
Restricted cash, cash equivalents, and short-term investments | 1,903,000 | 1,902,000
Fair value disclosure | Variable rate demand notes |  |
Fair value disclosure |  |
Cash and cash equivalents | 29,747,000 | 29,706,000
Fair value disclosure | Money market funds |  |
Fair value disclosure |  |
Cash and cash equivalents | 11,101,000 | 12,101,000
Fair value disclosure | Certificates of deposit |  |
Fair value disclosure |  |
Short-term investments | $ 35,960,000 | $ 35,906,000

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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 current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term 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. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 2: 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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- Definition Investments which are intended to be sold in the short term (usually less than one year or the normal operating cycle, whichever is longer) including trading securities, available-for-sale securities, held-to-maturity securities, and other short-term investments not otherwise listed in the existing taxonomy. + 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 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 1 -Subparagraph g -Article 7 + Details
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