Summary of Warrant Activity (Detail) - Warrants - $ / shares shares in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Shares | |||
| Beginning Balance | 11,406 | 10,094 | 10,094 |
| Granted/Issued | 3,926 | 2,035 | |
| Exercised | |||
| Forfeited, cancelled, or expired | (9,206) | (723) | |
| Ending Balance | 6,126 | 11,406 | 10,094 |
| Warrants exercisable, December 31, 2017 | 5,991 | ||
| Vested warrants expired during the 12 months ended December 31, 2017 | 9,206 | ||
| Weighted-Average Exercise Price Per Share | |||
| Beginning Balance | $ 4.18 | $ 4.18 | $ 4.18 |
| Granted/Issued | 1.80 | 2.00 | |
| Exercised | |||
| Forfeited, cancelled, or expired | 4.00 | 6.50 | |
| Ending Balance | 1.93 | $ 4.18 | $ 4.18 |
| Warrants exercisable, December 31, 2017 | 1.88 | ||
| Vested warrants expired during the 12 months ended December 31, 2017 | $ 4.00 | ||
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options exercisable number. No definition available.
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options exercisable weighted average exercise price. No definition available.
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- Definition Sharebased compensation arrangement by sharebased payment award equity instruments other than options expired in period. No definition available.
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options expired in period weighted average grant date fair value. No definition available.
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options forfeited, cancelled or expired in period weighted average grant date fair value. No definition available.
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- Definition Share based compensation arrangement by share based payment award equity instruments other than options weighted average exercise price. No definition available.
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- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Number of non-option equity instruments exercised by participants. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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