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Stock Based Compensation (Details) - Stock Options [Member] $ / shares in Units, $ in Thousands | 12 Months Ended
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Dec. 31, 2018 USD ($) $ / shares shares
Number of options: |  |
Number of Options outstanding, beginning | shares | 47,250 |
Options outstanding prior to stock dividend | shares | 47,250 |
Options outstanding after 5% stock dividend | shares | 49,613 | [1]
Options exercised after stock dividend | shares | (6,484) |
Options granted after stock dividend | $ | $ 15,000 |
Number of Options outstanding, ending | shares | 58,129 |
Number of Options exercisable | shares | 38,612 |
Weighted Average Exercise Price: |  |
Weighted Average Exercise Price of Options outstanding, beginning | $ 22.32 |
Options outstanding prior to stock dividend | 22.32 |
Options outstanding after 5% stock dividend | 21.26 | [1]
Options exercised after stock dividend | 21.08 |
Options granted after stock dividend | 25.65 |
Weighted Average Exercise Price of Options outstanding, ending | 22.41 |
Weighted Average Exercise Price of Options exercisable | $ 21.52 |
[1] | The 2018 balance was adjusted for the 5% stock dividend paid on May 31, 2018.

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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + References No definition available. + Details
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- Definition Weighted average price at which option holders acquired shares when converting their stock options into shares. + References No definition available. + Details
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