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Consolidated Statements of Changes in Shareholders' Equity - USD ($) | Preferred Stock [Member] | Common Stock [Member] | Retained Earnings [Member] | AOCI Attributable to Parent [Member] | Total
--- | --- | --- | --- | --- | ---
Beginning Balances at Dec. 31, 2013 | $ 0 | $ 162,999,000 | $ (4,101,000) | $ (5,573,000) | $ 153,325,000
Common stock issued in connection with Firstbank merger (8,087,272 shares) |  | 173,310,000 |  |  | 173,310,000
Issuance of stock options to replace existing Firstbank options at merger date |  | 1,664,000 |  |  | 1,664,000
Employee stock purchase plan |  | 23,000 |  |  | 23,000
Dividend reinvestment plan |  | 209,000 |  |  | 209,000
Stock option exercises |  | 282,000 |  |  | 282,000
Stock grants to directors for retainer fees |  | 155,000 |  |  | 155,000
Stock-based compensation expense |  | 714,000 |  |  | 714,000
Cash dividends |  | (21,452,000) | (3,012,000) |  | (24,464,000)
Net income |  |  | 17,331,000 |  | 17,331,000
Change in net unrealized gain on securities available for sale, net of tax effect |  |  |  | 5,582,000 | 5,582,000
Change in fair value of interest rate swap, net of tax effect |  |  |  | 7,000 | 7,000
Balances at Dec. 31, 2014 | 0 | 317,904,000 | 10,218,000 | 16,000 | 328,138,000
Employee stock purchase plan |  | 44,000 |  |  | 44,000
Dividend reinvestment plan |  | 655,000 |  |  | 655,000
Stock option exercises |  | 891,000 |  |  | 891,000
Stock grants to directors for retainer fees |  | 403,000 |  |  | 403,000
Stock-based compensation expense |  | 684,000 |  |  | 684,000
Cash dividends |  |  | (9,516,000) |  | (9,516,000)
Net income |  |  | 27,020,000 |  | 27,020,000
Change in net unrealized gain on securities available for sale, net of tax effect |  |  |  | 1,247,000 | 1,247,000
Change in fair value of interest rate swap, net of tax effect |  |  |  | 0 | 0
Balances at Dec. 31, 2015 | 0 | 304,819,000 | 27,722,000 | 1,263,000 | 333,804,000
Share repurchase program |  | (15,762,000) |  |  | (15,762,000)
Employee stock purchase plan |  | 36,000 |  |  | 36,000
Dividend reinvestment plan |  | 1,601,000 |  |  | 1,601,000
Stock option exercises |  | 978,000 |  |  | 978,000
Stock grants to directors for retainer fees |  | 327,000 |  |  | 327,000
Stock-based compensation expense |  | 1,459,000 |  |  | 1,459,000
Cash dividends |  |  | (18,731,000) |  | (18,731,000)
Net income |  |  | 31,913,000 |  | 31,913,000
Change in net unrealized gain on securities available for sale, net of tax effect |  |  |  | (6,954,000) | (6,954,000)
Change in fair value of interest rate swap, net of tax effect |  |  |  | 110,000 | 110,000
Balances at Dec. 31, 2016 | $ 0 | 305,488,000 | $ 40,904,000 | $ (5,581,000) | 340,811,000
Share repurchase program |  | $ (3,732,000) |  |  | $ (3,732,000)

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