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Condensed Consolidated Statement of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands | Total | Common Stock [Member] | Additional Paid-In Capital [Member] | Treasury Stock [Member] | Accumulated Earnings [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
--- | --- | --- | --- | --- | --- | ---
Beginning Balance at Dec. 31, 2016 |  |  |  |  |  | $ (492)
Comprehensive income | $ 14,476 |  |  |  |  |
Common stock issued upon exercise of options, Shares | 0 |  |  |  |  |
Ending Balance at Mar. 31, 2017 |  |  |  |  |  | 460
Beginning Balance at Dec. 31, 2017 | $ 425,423 | $ 204 | $ 210,081 | $ (22,370) | $ 233,896 | 3,612
Beginning Balance, Shares at Dec. 31, 2017 | 20,504,165 | 20,504,165 |  |  |  |
Treasury Stock Beginning Balance, Shares at Dec. 31, 2017 | (1,258,250) |  |  | (1,258,250) |  |
Comprehensive income | $ 10,321 |  |  |  | 16,169 | (5,848)
Impact of adoption of ASU | ASU 2016-01 [Member] | 615 |  |  |  | 615 |
Impact of adoption of ASU | ASU 2018-02 [Member] | (414) |  |  |  | (414) |
Common stock issued upon exercise of options | $ 68 | $ 1 | 67 |  |  |
Common stock issued upon exercise of options, Shares | 15,000 | 15,000 |  |  |  |
Share-based compensation | $ 293 |  | 293 |  |  |
Dividends to shareholders | (4,238) |  |  |  | (4,238) |
Ending Balance at Mar. 31, 2018 | $ 432,068 | $ 205 | $ 210,441 | $ (22,370) | $ 246,028 | $ (2,236)
Ending Balance, Shares at Mar. 31, 2018 | 20,519,165 | 20,519,165 |  |  |  |
Treasury Stock Ending Balance, Shares at Mar. 31, 2018 | (1,258,250) |  |  | (1,258,250) |  |

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- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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