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Equity Compensation and Employee Benefit Plans (Tables) | 12 Months Ended
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Dec. 31, 2017
Compensation and Retirement Disclosure [Abstract] |
Schedule of Equity Compensation Expense and Related Income Tax Benefit Recognized | The following table summarizes the equity compensation expense and related income tax benefit recognized in the Consolidated Statements of Income (in thousands):
|  | Years Ended December 31,
|  | 2017 |  | 2016 |  | 2015
Stock options: |  |  |  |  |  |
Pre-tax compensation expense |  | $ | 6 |  |  | $ | (25 | ) |  | $ | 30 |
Tax benefit |  | 2 |  |  | (9 | ) |  | 11 |
Stock option expense, net of tax |  | $ | 4 |  |  | $ | (16 | ) |  | $ | 19 |
Restricted awards: |  |  |  |  |  |
Pre-tax compensation expense |  | $ | 3,244 |  |  | $ | 2,337 |  |  | $ | 1,875 |
Tax benefit |  | 1,265 |  |  | 886 |  |  | 722 |
Restricted stock expense, net of tax |  | $ | 1,979 |  |  | $ | 1,451 |  |  | $ | 1,153 |
Performance awards: |  |  |  |  |  |
Pre-tax compensation expense |  | $ | 1,459 |  |  | $ | 167 |  |  | $ | 2,514 |
Tax benefit |  | 569 |  |  | 63 |  |  | 968 |
Performance award expense, net of tax |  | $ | 890 |  |  | $ | 104 |  |  | $ | 1,546 |
Schedule of Equity Compensation Stock Options Activity | The following table summarizes stock option activity for the year ended December 31, 2017:
| Number of Options (in thousands) |  | Weighted Average Exercise Price ($) |  | Weighted Average Remaining Contractual Term (Years) |  | Aggregate Intrinsic Value (in thousands)
Outstanding at beginning of period | 171 |  |  | $ | 18.19 |  |  |  |  |
Granted | — |  |  | — |  |  |  |  |
Exercised | (138 | ) |  | 17.83 |  |  |  |  |
Forfeited | — |  |  | — |  |  |  |  |
Expired | — |  |  | — |  |  |  |  |
Outstanding at end of period | 33 |  |  | 19.69 |  |  | 2.33 |  | $ | 623 |
Exercisable at end of period | 33 |  |  | 19.69 |  |  | 2.33 |  | $ | 623 |
Intrinsic Value of Stock Options Exercised | The total intrinsic value of stock options exercised was as follows (in thousands):
2017 | $ | 1,722 |
2016 | 119 |
2015 | 655 |
Schedule of Equity Compensation, Restricted Stock and Restricted Stock Units Activity | The following table summarizes restricted award activity for the year ended December 31, 2017:
| Number of Restricted Awards (in thousands) |  | Weighted Average Grant Date Fair Value ($)
Nonvested at beginning of period | 293 |  |  | $ | 25.98 |
Granted | 110 |  |  | 28.92 |
Vested | (119 | ) |  | 24.70 |
Forfeited | (11 | ) |  | 26.89 |
Nonvested at end of period | 273 |  |  | 27.69 |
Schedule of Equity Compensation Performance Award Activity | The following table summarizes performance award activity for the year ended December 31, 2017:
| Number of Performance Awards (in thousands) |  | Weighted Average Grant Date Fair Value ($)
Nonvested at beginning of period | 124 |  |  | $ | 27.33 |
Granted | 69 |  |  | 26.89 |
Vested | (35 | ) |  | 27.07 |
Forfeited | — |  |  | — |
Nonvested at end of period | 158 |  |  | 27.20 |
Contributions for Employee Stock Purchase Plan | Our contributions for the Purchase Plan were as follows (in thousands):
2017 | $ | 208 |
2016 | 183 |
2015 | 182 |
Contributions and Administrative Expenses Under 401(k) Retirement Savings Plan | Salaries, wages and benefits expense in the accompanying Consolidated Statements of Income includes our 401(k) Plan contributions and administrative expenses, which were as follows (in thousands):
2017 | $ | 2,357 |
2016 | 2,113 |
2015 | 2,041 |
Deferred Compensation Assets and Liabilities | The accumulated benefit obligation and aggregate market value of the life insurance policies were as follows (in thousands):
| December 31,
| 2017 |  | 2016
Accumulated benefit obligation | $ | 7,682 |  |  | $ | 6,920 |
Aggregate market value | 7,059 |  |  | 5,821 |

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- Definition Tabular disclosure of the amount of total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. + 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 (h)(1) -URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901 + Details
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- Definition Tabular disclosure of the costs related to the various types of retirement plans including defined benefit pension plan cost, defined contribution plan cost, other postretirement benefit plan cost, and net periodic benefit cost. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + 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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- Definition Disclosure of the number and weighted-average grant date fair value for restricted stock and restricted stock units that were outstanding at the beginning and end of the year, and the number of restricted stock and restricted stock units that were granted, vested, or forfeited during the year. + References No definition available. + Details
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