Shareholders' Equity and Capital Stock - options activity (Details) - $ / shares |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
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| Options Rollforward | |||
| Outstanding, Beginning Balance | 9,748,934 | 9,974,407 | 8,468,614 |
| Granted, Options | 2,666,644 | 3,062,542 | 2,384,052 |
| Exercised, Options | (871,717) | (16,620) | (608,531) |
| Forfeited, Options | (536,178) | (788,883) | (258,918) |
| Expired, Options | (1,548,282) | (2,482,512) | (10,810) |
| Outstanding Ending Balance, Options | 9,459,401 | 9,748,934 | 9,974,407 |
| Outstanding, Beginning Balance, Weighted-average exercise price | $ 0.63 | $ 0.88 | $ 1.12 |
| Granted, Weighted-average exercise price | 0.69 | 0.57 | 0.67 |
| Exercised, Weighted-average exercise price | 0.62 | 0.58 | 0.66 |
| Forfeited, Weighted-average exercise price | 0.64 | 0.70 | 1.09 |
| Expired, Weighted-average exercise price | 0.71 | 1.56 | 0.64 |
| Outstanding Ending Balance, Weighted-average exercise price | 0.70 | $ 0.63 | $ 0.88 |
| Grant date intrinsic value | $ 0 | ||
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- Definition Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition The grant-date intrinsic value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Gross number of share options (or share units) granted during the period. No definition available.
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- Definition Number of options outstanding, including both vested and non-vested options. 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 Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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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 price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired. No definition available.
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- Definition Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated. No definition available.
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- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
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- Definition Number of share options (or share units) exercised during the current period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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