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Consolidated Statements 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, 2018 | $ 409,762 | $ 205 | $ 211,431 | $ (22,370) | $ 221,328 | $ (832)
Beginning Balance, Shares at Dec. 31, 2018 |  | 20,528,230 |  | (1,258,250) |  |
Impact of adoption of ASU | ASU 2016-02 [Member] | (1) |  |  |  | (1) |
Comprehensive income: |  |  |  |  |  |
Net income | 37,290 |  |  |  | 37,290 |
Other comprehensive income: |  |  |  |  |  |
Change in unrealized gains (losses), net of tax | 10,972 |  |  |  |  | 10,972
Comprehensive income | 48,262 |  |  |  |  |
Common stock issued upon exercise of options | $ 20 |  | 20 |  |  |
Common stock issued upon exercise of options, Shares | 5,000 | 5,000 |  |  |  |
Common stock issued | $ 560 |  | 560 |  |  |
Common stock issued, Shares |  | 23,281 |  |  |  |
Share-based compensation | 482 |  | 482 |  |  |
Dividends to shareholders | (9,642) |  |  |  | (9,642) |
Ending Balance at Jun. 30, 2019 | 449,443 | $ 205 | 212,493 | $ (22,370) | 248,975 | 10,140
Ending Balance, Shares at Jun. 30, 2019 |  | 20,556,511 |  | (1,258,250) |  |
Beginning Balance at Mar. 31, 2019 | 430,405 | $ 205 | 211,700 | $ (22,370) | 235,908 | 4,962
Beginning Balance, Shares at Mar. 31, 2019 |  | 20,533,230 |  | (1,258,250) |  |
Comprehensive income: |  |  |  |  |  |
Net income | 17,890 |  |  |  | 17,890 |
Other comprehensive income: |  |  |  |  |  |
Change in unrealized gains (losses), net of tax | 4,980 |  |  |  |  | 4,980
Change in deferred tax valuation allowance | 198 |  |  |  |  | 198
Comprehensive income | 23,068 |  |  |  |  |
Common stock issued | 560 |  | 560 |  |  |
Common stock issued, Shares |  | 23,281 |  |  |  |
Share-based compensation | 233 |  | 233 |  |  |
Dividends to shareholders | (4,823) |  |  |  | (4,823) |
Ending Balance at Jun. 30, 2019 | 449,443 | $ 205 | 212,493 | $ (22,370) | 248,975 | 10,140
Ending Balance, Shares at Jun. 30, 2019 |  | 20,556,511 |  | (1,258,250) |  |
Beginning Balance at Dec. 31, 2019 | $ 430,215 | $ 205 | 213,004 | $ (22,370) | 227,165 | 12,211
Beginning Balance, Shares at Dec. 31, 2019 | 19,302,583 | 20,560,833 |  | (1,258,250) |  |
Impact of adoption of ASU | ASU 2016-13 [Member] | $ (594) |  |  |  | (594) |
Comprehensive income: |  |  |  |  |  |
Net income | 34,748 |  |  |  | 34,748 |
Other comprehensive income: |  |  |  |  |  |
Change in unrealized gains (losses), net of tax | 6,967 |  |  |  |  | 6,967
Comprehensive income | $ 41,715 |  |  |  |  |
Common stock issued upon exercise of options, Shares | 0 |  |  |  |  |
Common stock issued | $ 1,360 | $ 1 | 1,359 |  |  |
Common stock issued, Shares |  | 28,476 |  |  |  |
Share-based compensation | 531 |  | 531 |  |  |
Dividends to shareholders | (10,431) |  |  |  | (10,431) |
Ending Balance at Jun. 30, 2020 | $ 462,796 | $ 206 | 214,894 | $ (22,370) | 250,888 | 19,178
Ending Balance, Shares at Jun. 30, 2020 | 19,331,059 | 20,589,309 |  | (1,258,250) |  |
Beginning Balance at Mar. 31, 2020 | $ 436,956 | $ 205 | 213,267 | $ (22,370) | 232,159 | 13,695
Beginning Balance, Shares at Mar. 31, 2020 |  | 20,561,034 |  | (1,258,250) |  |
Comprehensive income: |  |  |  |  |  |
Net income | 23,948 |  |  |  | 23,948 |
Other comprehensive income: |  |  |  |  |  |
Change in unrealized gains (losses), net of tax | 5,483 |  |  |  |  | 5,483
Comprehensive income | 29,431 |  |  |  |  |
Common stock issued | 1,360 | $ 1 | 1,359 |  |  |
Common stock issued, Shares |  | 28,275 |  |  |  |
Share-based compensation | 268 |  | 268 |  |  |
Dividends to shareholders | (5,219) |  |  |  | (5,219) |
Ending Balance at Jun. 30, 2020 | $ 462,796 | $ 206 | $ 214,894 | $ (22,370) | $ 250,888 | $ 19,178
Ending Balance, Shares at Jun. 30, 2020 | 19,331,059 | 20,589,309 |  | (1,258,250) |  |

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