Summary of Option Activity (Detail) - $ / shares shares in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
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| Shares | |||
| Beginning Balance | 1,347 | 1,322 | 898 |
| Granted at fair market value | 611 | 446 | 622 |
| Exercised | (1) | ||
| Forfeited, cancelled, or expired | (334) | (421) | (198) |
| Ending Balance | 1,623 | 1,347 | 1,322 |
| Options exercisable, December 31, 2018 | 1,101 | ||
| Vested options expired during the twelve months ended December 31, 2018 | 102 | ||
| Weighted-Average Exercise Price Per Share | |||
| Beginning Balance | $ 8.99 | $ 13.60 | $ 15.15 |
| Granted at fair market value | 1.98 | 5.15 | 7.10 |
| Exercised | 2.10 | 4.30 | |
| Forfeited, cancelled, or expired | 10.68 | 9.15 | 15.05 |
| Ending Balance | 6.54 | $ 8.99 | $ 13.60 |
| Options exercisable, December 31, 2018 | 7.88 | ||
| Vested options expired during the twelve months ended December 31, 2018 | $ 18.06 | ||
| Weighted-Average Remaining Contractual Term (Years) | |||
| Options outstanding | 5 years 11 months 8 days | ||
| Options exercisable | 4 years 11 months 23 days | ||
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- Definition Share based compensation arrangement by share based payment award options grants in period at fair market value. No definition available.
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- Definition Share based compensation arrangement by share based payment award options weighted average remaining contractual term. No definition available.
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- Definition Share based compensation arrangement by share based payment award vested options expirations in period. No definition available.
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- Definition Share based compensation arrangement by share based payment award vested options expirations in period weighted average exercise price. No definition available.
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- Definition Share based compensation arrangements by share based payment award options grants in period weighted average exercise price at fair market value. No definition available.
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- Definition The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average price of options that were either forfeited or expired. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. No definition available.
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- Definition Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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