Marketable Securities and Fair Value - Additional Information (Detail) - USD ($) shares in Millions |
3 Months Ended | 6 Months Ended | ||
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Jun. 30, 2015 |
Jun. 30, 2014 |
Jun. 30, 2015 |
Jun. 30, 2014 |
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Schedule Of Available For Sale Securities [Line Items] | ||||
Realized gain or losses | $ 0 | $ 0 | $ 0 | $ 0 |
Weighted average maturity for available for sale securities | 4 months 3 days | |||
February 2015 and March 2011 Offering | ||||
Schedule Of Available For Sale Securities [Line Items] | ||||
Shares of common stock to be purchased with warrants | 12.1 | 12.1 | ||
Maximum | ||||
Schedule Of Available For Sale Securities [Line Items] | ||||
Available for sale securities, longest maturity date | 2016-05 |
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- Definition Available for sale securities, longest maturity date. No definition available.
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- Definition Weighted average maturity for available for sale securities. No definition available.
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- Definition This item represents the difference between the gross realized gains and losses realized on the sale of debt or equity securities categorized neither as held-to-maturity nor trading securities. Additionally, this item would include any losses recognized for other than temporary impairments (OTTI) of the subject investments in debt and equity securities. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of warrants or rights outstanding. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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