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Incentive and Restricted Stock Plan and Dividend Reinvestment Plan - Additional Information (Details) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Number of awards outstanding (in shares) | 0 | 0 | 155,500 | 428,900
Nonstatutory stock options granted since 2006 (in shares) | 0 | 0 | 0 |
Aggregate intrinsic value of options outstanding |  |  | $ 0 |
Aggregate intrinsic value of options exercisable |  |  | 0 |
Unrecognized compensation expense to be recognized | $ 2,500,000 |  |  |
Weighted average compensation expense recognize period | 1 year 6 months 30 days |  |  |
Restricted Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Compensation expense | $ 2,500,000 | $ 1,700,000 | 900,000 |
Tax benefit realized on compensation expense | $ 900,000 | $ 600,000 | $ 300,000 |
2014 Stock Plan |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Maximum number of common stock authorized (in shares) | 750,000 |  |  |
Stock plan expiration period | 10 years |  |  |
Number of awards outstanding (in shares) | 0 |  |  |
2014 Stock Plan | Restricted Stock |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted shares granted | 110,643 | 87,841 |  |
2014 Stock Plan | Restricted Stock | Employees and Directors |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted shares granted | 278,939 |  |  |
2014 Stock Plan | Restricted Stock | Outside Directors |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 1 year |  |  |
Restricted shares granted | 15,613 | 16,142 | 13,824 |
LTIP | Time-based and Performance-based Restricted Stocks | Senior Management |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted shares granted | 95,030 | 71,699 | 66,631 |
LTIP | Time-based Restricted Shares | Senior Management |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Restricted Stock Award vesting after year two, percent | 50.00% |  |  |
Restricted Stock Award vesting after year three, percent | 50.00% |  |  |
LTIP | Performance-based Restricted Shares | Senior Management |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |
Vesting period | 3 years |  |  |

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- Definition Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 14.F) -URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (h)(1)(i) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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