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Incentive and Restricted Stock Plan and Dividend Reinvestment Plan (Tables) | 12 Months Ended
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Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of Nonstatutory Stock Options Activity | The following table summarizes activity for nonstatutory stock options for the years ended December 31:
| 2015 |  | 2014 |  | 2013
| Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Term |  | Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Term |  | Number of Shares |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Term
Outstanding at beginning of year | 155,500 |  | $ | 37.86 |  |  |  | 428,900 |  | $ | 37.36 |  |  |  | 675,500 |  | $ | 35.18 |  |
Granted | — |  | — |  |  |  | — |  | — |  |  |  | — |  | — |  |
Exercised | — |  | — |  |  |  | — |  | — |  |  |  | — |  | — |  |
Forfeited | — |  | — |  |  |  | (273,400 | ) | 37.08 |  |  |  | (246,600 | ) | 31.39 |  |
Expired | (155,500 | ) | 37.86 |  |  |  | — |  | — |  |  |  | — |  | — |  |
Outstanding at End of Year | — |  | — |  | 0.0 years |  | 155,500 |  | $ | 37.86 |  | 1.0 year |  | 428,900 |  | $ | 37.36 |  | 1.4 years
Exercisable at End of Year | — |  | — |  | 0.0 years |  | 155,500 |  | $ | 37.86 |  | 1.0 year |  | 428,900 |  | $ | 37.36 |  | 1.4 years
2003 Stock Plan |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of Non-Vested Restricted Stock | The following table provides information about restricted stock granted under the 2003 Stock Plan for the years ended December 31:
| Restricted Stock |  |  | Weighted Average Grant Date Fair Value |
Non-vested at December 31, 2013 | 79,415 |  |  | $ | 21.50 |
Granted | — |  |  | — |
Vested | 41,740 |  |  | 20.70 |
Forfeited | 14,530 |  |  | 20.97 |
Non-vested at December 31, 2014 | 23,145 |  |  | $ | 23.28 |
Granted | — |  |  | — |
Vested | 15,433 |  |  | 22.34 |
Forfeited | 7,712 |  |  | 22.34 |
Non-vested at December 31, 2015 | — |  |  | $ | — |
2014 Stock Plan |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of Non-Vested Restricted Stock | The following table provides information about restricted stock granted under the 2014 Stock Plan for the years ended December 31:
| Restricted Stock |  |  | Weighted Average Grant Date Fair Value |
Non-vested at December 31, 2013 | — |  |  | $ | — |
Granted | 80,455 |  |  | 23.24 |
Vested | 158 |  |  | 23.19 |
Forfeited | 473 |  |  | 23.19 |
Non-vested at December 31, 2014 | 79,824 |  |  | $ | 23.24 |
Granted | 87,841 |  |  | 28.71 |
Vested | 14,126 |  |  | 23.57 |
Forfeited | 3,183 |  |  | 26.15 |
Non-vested at December 31, 2015 | 150,356 |  |  | $ | 26.34 |

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- Definition Tabular disclosure of the changes in outstanding nonvested restricted stock units. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the number and weighted-average exercise prices (or conversion ratios) for share options (or share units) that were outstanding at the beginning and end of the year, vested and expected to vest, exercisable or convertible at the end of the year, and the number of share options or share units that were granted, exercised or converted, forfeited, and expired during the year. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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