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Equity-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2016
Share-based Compensation [Abstract] |
PSUs Eligible for Conversion to Cash | The following table provides the number of PSUs which will convert to cash for the years ending December 31:
| 2016 |  | 2015 |  | 2014
Awards | Number of Units (1) |  | Grant Date Fair Value (in $000s) |  | Number of Units (2) |  | Grant Date Fair Value (in $000s) |  | Number of Units (3) |  | Grant Date Fair Value (in $000s)
Performance stock units | 128,000 |  |  | $ | 3,100 |  |  | 219,000 |  |  | $ | 4,039 |  |  | 231,000 |  |  | $ | 4,233 |
(1) The participants earned 200% of target aggregating 256,000 PSUs earned. This award will convert to cash and be payable in January 2019. (2) The participants earned 200% of target aggregating 438,000 PSUs earned. This award will convert to cash and be payable in January 2018. (3) Based on the actual 2014 ROIC, no shares were earned during the performance period.
Schedule of Number of Awards and Weighted Average Grant Date Fair Value | The following table provides the number of stock unit awards granted which will convert to shares upon vesting as well as restricted shares issued during the years ended December 31, along with the weighted-average grant-date fair value of each award:
| 2016 |  | 2015 |  | 2014
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
Deferred stock units | 11,945 |  |  | $ | 29.30 |  |  | — |  |  | $ | — |  |  | — |  |  | $ | — |
Options | — |  |  | $ | — |  |  | 37,500 |  |  | $ | 25.44 |  |  | — |  |  | $ | — |
Restricted shares | 3,185 |  |  | $ | 29.30 |  |  | 21,318 |  |  | $ | 17.48 |  |  | 21,721 |  |  | $ | 16.76 |
Restricted stock units | 141,982 |  |  | $ | 25.44 |  |  | 212,419 |  |  | $ | 17.78 |  |  | 218,857 |  |  | $ | 16.96 |
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):
| 2016 |  | 2015 |  | 2014
Expense recognized under the Prior Plan | $ | 1,937 |  |  | $ | 1,953 |  |  | $ | 3,150 |
Expense recognized under the Plan | 3,993 |  |  | 1,938 |  |  | — |
Expense recognized under the Non-Employee Directors Plan | 443 |  |  | — |  |  | — |
Total stock compensation expense | $ | 6,373 |  |  | $ | 3,891 |  |  | $ | 3,150 |
Tax benefits recognized related to stock compensation expense | $ | 2,485 |  |  | $ | 1,518 |  |  | $ | 1,229 |
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions |
| 2016 |  | 2015 |  | 2014
Expense recognized under the Prior Plan | $ | 1,937 |  |  | $ | 1,953 |  |  | $ | 3,150 |
Expense recognized under the Plan | 3,993 |  |  | 1,938 |  |  | — |
Expense recognized under the Non-Employee Directors Plan | 443 |  |  | — |  |  | — |
Total stock compensation expense | $ | 6,373 |  |  | $ | 3,891 |  |  | $ | 3,150 |
Tax benefits recognized related to stock compensation expense | $ | 2,485 |  |  | $ | 1,518 |  |  | $ | 1,229 |
The fair value of the restricted shares, restricted stock units, and performance stock units issued during the three years ended December 31, 2016
Summary of Ranges of Outstanding and Exercisable Options | The following table summarizes the ranges of outstanding and exercisable options at December 31, 2016:
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 | 36,500 |  |  | 3.70 |  | $ | 8.90 |  |  | 36,500 |  |  | $ | 8.90 |
$9.74 – $9.74 | 95,441 |  |  | 4.70 |  | $ | 9.74 |  |  | 95,441 |  |  | $ | 9.74 |
$11.89 – $18.78 | 70,783 |  |  | 1.85 |  | $ | 15.78 |  |  | 70,783 |  |  | $ | 15.78 |
$20.52 – $23.78 | 37,000 |  |  | 1.69 |  | $ | 22.16 |  |  | 37,000 |  |  | $ | 22.16 |
$23.79 – $25.44 | 37,500 |  |  | 9.00 |  | $ | 25.44 |  |  | — |  |  | $ | — |
| 277,224 |  |  |  |  |  |  | 239,724 |  |  |
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, 2014 | 622,124 |  |  | $ | 15.48 |  |  |  |  |
Exercised | (52,805 | ) |  | 11.18 |  |  |  |  |
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 |  |  |  |  |
Exercised | (175,125 | ) |  | 19.08 |  |  |  |  |
Forfeited | (6,000 | ) |  | 18.22 |  |  |  |  |
Balance at December 31, 2016 | 277,224 |  |  | $ | 14.95 |  |  | 4.02 |  | $ | 7,401,000 |
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):
| 2016 |  | 2015 |  | 2014
Aggregate intrinsic value of options exercised | $ | 2,439 |  |  | $ | 1,089 |  |  | $ | 326 |
Aggregate fair value of vested restricted stock units | $ | 4,368 |  |  | $ | 6,578 |  |  | $ | 2,416 |
Aggregate fair value of vested restricted shares | $ | 247 |  |  | $ | 111 |  |  | $ | 364 |
Aggregate fair value of vested deferred stock units | $ | 443 |  |  | $ | — |  |  | $ | — |
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 |  | Deferred Stock Units (1) |  | Weighted Average Grant Date Fair Value
Balance at December 31, 2015 | 548,815 |  |  | $ | 15.22 |  |  | 21,485 |  |  | $ | 17.59 |  |  | 396,714 |  |  | $ | 19.78 |  |  | — |  |  | $ | — |
Granted | 141,982 |  |  | 25.44 |  |  | 3,185 |  |  | 29.30 |  |  | — |  |  | — |  |  | 11,945 |  |  | 29.30 |
Vested | (131,369 | ) |  | 15.64 |  |  | (17,309 | ) |  | 19.65 |  |  | — |  |  | — |  |  | — |  |  | — |
Forfeited | (23,264 | ) |  | 16.18 |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |  |  | — |
Balance at December 31, 2016 | 536,164 |  |  | $ | 17.79 |  |  | 7,361 |  |  | $ | 17.07 |  |  | 396,714 |  |  | $ | 19.78 |  |  | 11,945 |  |  | $ | 29.30 |
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):
| 2016 |  | 2015 |  | 2014
Performance stock unit compensation expense | $ | 10,377 |  |  | $ | 6,965 |  |  | $ | 31 |
Cash Paid to Settle Liability Awards | The following table provides the number of restricted stock units credited to participant accounts, balance of vested and unvested restricted stock units within participant accounts, payments made with respect to restricted stock units issued under the MSPP, and MSPP expense during years ended December 31:
| 2016 |  | 2015 |  | 2014
Restricted stock units credited | 198,155 |  |  | 94,047 |  |  | 119,105 |
Restricted stock units balance, vested and unvested | 646,669 |  |  | 519,668 |  |  | 647,371 |
Share-based liabilities paid (in thousands) | $ | 3,137 |  |  | $ | 1,901 |  |  | $ | 2,120 |
MSPP expense (in thousands) | $ | 8,565 |  |  | $ | 2,767 |  |  | $ | 329 |

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