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Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) | Preferred Stock [Member] | Common Stock Including Additional Paid in Capital [Member] | Retained Earnings [Member] | AOCI Attributable to Parent [Member] | Total
--- | --- | --- | --- | --- | ---
Balances at Dec. 31, 2017 | $ 0 | $ 309,772,000 | $ 61,001,000 | $ (4,903,000) | $ 365,870,000
Employee stock purchase plan |  | 26,000 |  |  | 26,000
Dividend reinvestment plan |  | 328,000 |  |  | 328,000
Stock option exercises |  | 55,000 |  |  | 55,000
Stock grants to directors for retainer fees |  | 403,000 |  |  | 403,000
Stock-based compensation expense |  | 1,136,000 |  |  | 1,136,000
Cash dividends |  |  | (7,202,000) |  | (7,202,000)
Net income |  |  | 20,327,000 |  | 20,327,000
Change in net unrealized holding gain/(loss) on securities available for sale, net of tax effect |  |  |  | (6,025,000) | (6,025,000)
Reclassification of equity securities related to ASU 2016-01 adoption |  |  | (42,000) | 42,000 | 0
Change in fair value of interest rate swap, net of tax effect |  |  |  | 1,000 | 1,000
Balances at Jun. 30, 2018 | 0 | 311,720,000 | 74,084,000 | (10,885,000) | 374,919,000
Balances at Mar. 31, 2018 | 0 | 310,601,000 | 68,241,000 | (10,502,000) | 368,340,000
Employee stock purchase plan |  | 12,000 |  |  | 12,000
Dividend reinvestment plan |  | 164,000 |  |  | 164,000
Stock grants to directors for retainer fees |  | 403,000 |  |  | 403,000
Stock-based compensation expense |  | 540,000 |  |  | 540,000
Cash dividends |  |  | (3,603,000) |  | (3,603,000)
Net income |  |  | 9,446,000 |  | 9,446,000
Change in net unrealized holding gain/(loss) on securities available for sale, net of tax effect |  |  |  | (383,000) | (383,000)
Balances at Jun. 30, 2018 | 0 | 311,720,000 | 74,084,000 | (10,885,000) | 374,919,000
Balances at Dec. 31, 2018 | 0 | 308,005,000 | 75,483,000 | (8,239,000) | 375,249,000
Employee stock purchase plan |  | 26,000 |  |  | 26,000
Dividend reinvestment plan |  | 361,000 |  |  | 361,000
Stock option exercises |  | 16,000 |  |  | 16,000
Stock grants to directors for retainer fees |  | 374,000 |  |  | 374,000
Stock-based compensation expense |  | 1,488,000 |  |  | 1,488,000
Cash dividends |  |  | (8,404,000) |  | (8,404,000)
Net income |  |  | 23,539,000 |  | 23,539,000
Change in net unrealized holding gain/(loss) on securities available for sale, net of tax effect |  |  |  | 11,069,000 | 11,069,000
Share repurchase program |  | (3,601,000) |  |  | (3,601,000)
Balances at Jun. 30, 2019 | 0 | 306,669,000 | 90,618,000 | 2,830,000 | 400,117,000
Balances at Mar. 31, 2019 | 0 | 305,346,000 | 83,107,000 | (4,724,000) | 383,729,000
Employee stock purchase plan |  | 12,000 |  |  | 12,000
Dividend reinvestment plan |  | 179,000 |  |  | 179,000
Stock option exercises |  | 14,000 |  |  | 14,000
Stock grants to directors for retainer fees |  | 374,000 |  |  | 374,000
Stock-based compensation expense |  | 744,000 |  |  | 744,000
Cash dividends |  |  | (4,204,000) |  | (4,204,000)
Net income |  |  | 11,715,000 |  | 11,715,000
Change in net unrealized holding gain/(loss) on securities available for sale, net of tax effect |  |  |  | 7,554,000 | 7,554,000
Balances at Jun. 30, 2019 | $ 0 | $ 306,669,000 | $ 90,618,000 | $ 2,830,000 | $ 400,117,000

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