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Equity-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2015
Share-based Compensation [Abstract] |
Schedule of Number of Awards and Weighted Average Grant Date Fair Value | The following table provides the number of options, shares of restricted stock, as well as, restricted stock units and performance stock units (that will convert to shares upon vesting) that were issued during the years ended December 31 along with the weighted-average grant-date fair value of each award:
| 2015 |  | 2014 |  | 2013
Awards | Number of Awards |  | Weighted Average Grant Date Fair Value |  | Number of Awards |  | Weighted Average Grant Date Fair Value |  | Number of Awards |  | Weighted Average Grant Date Fair Value
Restricted stock units | 212,419 |  |  | $ | 17.78 |  |  | 218,857 |  |  | $ | 16.96 |  |  | 150,570 |  |  | $ | 14.60 |
Restricted shares | 21,318 |  |  | $ | 17.48 |  |  | 21,721 |  |  | $ | 16.76 |  |  | 13,188 |  |  | $ | 16.83 |
Options | 37,500 |  |  | $ | 25.44 |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Performance stock units | 396,714 |  |  | $ | 19.78 |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Summary of Compensation Expense Connection with Awards | The Company recognized the following compensation expense in connection with awards that vested under the Plan and the Prior Plan along with the related tax benefits recognized during the years ended December 31 (in thousands):
| 2015 |  | 2014 |  | 2013
Expense recognized under the Prior Plan | $ | 1,953 |  |  | $ | 3,150 |  |  | $ | 2,564 |
Expense recognized under the Plan | 1,938 |  |  | — |  |  | — |
Total stock compensation expense | $ | 3,891 |  |  | $ | 3,150 |  |  | $ | 2,564 |
Tax benefits recognized related to stock compensation expense | $ | 1,518 |  |  | $ | 1,229 |  |  | $ | 1,000 |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions | The following table provides the weighted average assumptions used to value stock options issued during the year ended December 31:
Year of Grant |  | Fair Value |  | Expected Life (in years) |  | Expected Stock Volatility |  | Risk-free Interest Rate |  | Annual Forfeiture Rate |  | Expected Dividend Yield
2015 |  | $ | 7.67 |  |  | 4.00 |  | 35.7 | % |  | 1.5 | % |  | — | % |  | — | %
Summary of Ranges of Outstanding and Exercisable Options | The following table summarizes the ranges of outstanding and exercisable options at December 31, 2015:
Range of Exercise Prices | Options Outstanding |  | Weighted Average Remaining Contractual Life (in years) |  | Weighted Average Exercise Price |  | Options Exercisable |  | Weighted Average Exercise Price
$8.90 – $8.90 | 42,000 |  |  | 4.63 |  | $ | 8.90 |  |  | 42,000 |  |  | $ | 8.90 |
$9.74 – $9.74 | 121,941 |  |  | 5.63 |  | $ | 9.74 |  |  | 121,941 |  |  | $ | 9.74 |
$11.89 – $18.78 | 117,033 |  |  | 2.52 |  | $ | 16.14 |  |  | 117,033 |  |  | $ | 16.14 |
$20.52 – $23.78 | 139,875 |  |  | 1.68 |  | $ | 22.81 |  |  | 139,875 |  |  | $ | 22.81 |
$23.79 – $25.44 | 37,500 |  |  | 9.93 |  | $ | 25.44 |  |  | — |  |  | $ | — |
| 458,349 |  |  |  |  |  |  | 420,849 |  |  |
Summary of Stock Options Transactions | The following table summarizes information about stock option transactions:
| Options |  | Weighted Average Exercise Price |  | Weighted Average Remaining Contractual Life (in years) |  | Aggregate Intrinsic Value
Balance at January 1, 2013 | 711,624 |  |  | $ | 14.97 |  |  |  |  |
Exercised | (59,750 | ) |  | 11.00 |  |  |  |  |
Forfeited | (29,750 | ) |  | 12.38 |  |  |  |  |
Balance at December 31, 2013 | 622,124 |  |  | $ | 15.48 |  |  |  |  |
Exercised | (52,805 | ) |  | 11.18 |  |  |  |  |
Forfeited | — |  |  | — |  |  |  |  |
Balance at December 31, 2014 | 569,319 |  |  | $ | 15.88 |  |  |  |  |
Granted | 37,500 |  |  | 25.44 |  |  |  |  |
Exercised | (119,096 | ) |  | 15.13 |  |  |  |  |
Forfeited | (750 | ) |  | 9.74 |  |  |  |  |
Expired | (28,624 | ) |  | 20.56 |  |  |  |  |
Balance at December 31, 2015 | 458,349 |  |  | $ | 16.57 |  |  | 3.42 |  | $ | 4,065,000 |
Aggregate Intrinsic Value of Options Exercised and Aggregate Fair Value of Restricted Stock Units and Restricted Shares that Vested | The following table sets forth the aggregate intrinsic value of options exercised and aggregate fair value of restricted stock units and restricted shares that vested during the years ended December 31 (in thousands):
| 2015 |  | 2014 |  | 2013
Aggregate intrinsic value of options exercised | $ | 1,089 |  |  | $ | 326 |  |  | $ | 398 |
Aggregate fair value of vested restricted stock units | $ | 6,578 |  |  | $ | 2,416 |  |  | $ | 1,900 |
Aggregate fair value of vested restricted shares | $ | 111 |  |  | $ | 364 |  |  | $ | 222 |
Summary of Information About Restricted Stock Units and Weighted Average Grant Date Fair Value | The following table summarizes information about non-vested restricted stock units and performance stock units (that will convert to shares upon vesting) and restricted shares:
| Restricted Stock Units |  | Weighted Average Grant Date Fair Value |  | Restricted Shares |  | Weighted Average Grant Date Fair Value |  | Performance Stock Units |  | Weighted Average Grant Date Fair Value
Balance at December 31, 2014 | 647,492 |  |  | $ | 15.26 |  |  | 10,259 |  |  | $ | 15.89 |  |  | — |  |  | $ | — |
Granted | 212,419 |  |  | 17.78 |  |  | 21,318 |  |  | 17.48 |  |  | 396,714 |  |  | 19.78 |
Vested | (297,080 | ) |  | 17.13 |  |  | (7,156 | ) |  | 15.49 |  |  | — |  |  | — |
Forfeited | (14,016 | ) |  | 15.43 |  |  | (2,936 | ) |  | 17.71 |  |  | — |  |  | — |
Balance at December 31, 2015 | 548,815 |  |  | $ | 15.22 |  |  | 21,485 |  |  | $ | 17.59 |  |  | 396,714 |  |  | $ | 19.78 |
Schedule of Compensation Expense Recognized from Change in Fair Value and Vesting of Performance Stock Units | The following table summarizes the compensation expense recognized from the change in fair value and vesting of performance stock units awarded for the years ended December 31 (in thousands):
| 2015 |  | 2014 |  | 2013
Performance stock unit compensation expense | $ | 6,965 |  |  | $ | 31 |  |  | $ | 2,214 |
Cash Paid to Settle Liability Awards | The MSPP is a share-based liability settled in cash. The following table sets forth the cash paid to settle these liability awards and expense recognized for the years ended December 31 (in thousands):
| 2015 |  | 2014 |  | 2013
Share-based liabilities paid | $ | 1,901 |  |  | $ | 2,120 |  |  | $ | 531 |
MSPP expense | $ | 2,767 |  |  | $ | 329 |  |  | $ | 3,857 |

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