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Financial Instruments and Marketable Securities - Additional Information (Details) (USD $) | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013
Financial Instruments and Marketable Securities [Abstract] |  |  |  |
Dollar value of transfers between levels | $ 0 | $ 0 | $ 0 | $ 0

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- Details
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- Definition Marketable Security Level Transfers + References No definition available. + Details
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