Note 10 - Stock-based Compensation - Changes in Shares Under Option Plans (Details) - $ / shares |
6 Months Ended | |
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Jun. 30, 2016 |
Jun. 30, 2015 |
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Beginning balance (in shares) | 298,740 | 759,683 |
Beginning balance (in dollars per share) | $ 9.97 | $ 11.36 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | 1,500 | |
Issued (in dollars per share) | $ 49.91 | |
Exercised (in shares) | (22,669) | (369,952) |
Exercised (in dollars per share) | $ 12.82 | $ 12.70 |
Forfeited (in shares) | (1,100) | (1,650) |
Forfeited (in dollars per share) | $ 15.48 | $ 15.48 |
Expired (in shares) | (6,037) | (8,007) |
Expired (in dollars per share) | $ 13.57 | $ 16.90 |
Ending balance (in shares) | 270,434 | 380,074 |
Ending balance (in dollars per share) | $ 9.85 | $ 9.92 |
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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 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 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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