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2012 Incentive Compensation Plan - Additional Information (Detail) - USD ($) |  |  | 7 Months Ended | 12 Months Ended
--- | --- | --- | --- | ---
Jul. 06, 2015 | Apr. 29, 2011 | Dec. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares authorized for stock-based compensation |  |  |  |  | 65,772 |
Number of shares granted to employees |  |  | 790,865 | 790,865 |  |
Anticipated volatility factor and zero dividend yield |  | 50.00% |  |  |  |
Expenses for the SAR granted |  |  |  | $ 160,000 | $ 329,000 | $ 907,000
Employee Stock Option 2012 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Restricted stock agreement vesting |  |  |  | These shares of Restricted Stock vest in various increments and periods over a maximum of ten years from the date the stock was granted as defined under the applicable Restricted Stock Award Agreement. |  |
Stock Compensation Plan [Member] | 2012 Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Shares authorized for stock-based compensation |  |  | 1,530,925 | 1,530,925 |  |
Common stock available for further issuance |  |  | 740,060 | 740,060 |  |
SAR I Award Agreement Amended [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Unvested portion of the company's common stock | 181,290 |  |  |  |  |
Deferred vesting period | 30 days |  |  |  |  |
SAR I Award Agreement Amended [Member] | Tranche One [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of vesting shares | 100,000 |  |  |  |  |
SAR I Award Agreement Amended [Member] | Tranche Two [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Number of vesting shares | 81,290 |  |  |  |  |
SAR I Award Agreement Amended [Member] | Deferred Bonus Granted in 2016 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Amount of annual bonus | $ 250,000 |  |  |  |  |
SAR I Award Agreement Amended [Member] | Deferred Bonus Granted in 2017 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Amount of annual bonus | 250,000 |  |  |  |  |
SAR I Award Agreement Amended [Member] | Deferred Bonus Granted in 2018 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Amount of annual bonus | 250,000 |  |  |  |  |
SAR I Award Agreement Amended [Member] | Deferred Bonus Granted in 2019 [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Amount of annual bonus | $ 250,000 |  |  |  |  |
SAR I [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Expected term |  |  | 4 years 10 months 24 days | 6 years |  |
Risk-free interest rate |  |  | 1.53% | 0.92% |  |
Dividend yield |  |  | $ 0 | $ 0 |  |
Anticipated volatility factor and zero dividend yield |  |  | 50.00% | 55.00% |  |
Discount on valuation of trading activity |  |  | 15.00% | 15.00% |  |
Fair value of SAR granted |  |  | $ 1.54 | $ 3.31 |  |
Compensation expenses |  |  |  | $ 1,800,000 |  |
Total unrecognized compensation expense |  |  | $ 333,000 | $ 333,000 |  |
Market value of the Company's common stock |  |  | $ 51.14 | $ 51.14 |  |
Exercise price |  |  | $ 22.07 | 22.07 |  |
Total expected expense from initial grant |  |  | $ 2,133,000 |  |  |
Unrecognized compensation expense |  |  | $ 259,000 |  |  |
Restricted Stock [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Fair value of SAR granted |  |  |  | $ 28.48 | $ 71.47 |
Compensation expenses |  |  |  | $ 989,000 | $ 925,000 | $ 361,000
Unvested portion of the company's common stock |  |  | 130,244 | 130,244 | 154,251 | 162,993
Number of vesting shares |  |  |  | 24,207 | 19,742 |
Expected period of recognition of cost |  |  |  | 6 years |  |
Restricted stock activity, amount |  |  |  |  |  | $ 0
Restricted stock activity, shares granted |  |  |  |  |  | 162,993
Fair value of restricted stock vested |  |  |  | $ 1,101,000 | $ 1,408,000 |
Restricted Stock [Member] | 2012 Plan [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Total unrecognized compensation expense |  |  | $ 4,882,000 | $ 4,882,000 |  |
Restricted Stock [Member] | Maximum [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Vesting period for restricted stock |  |  |  | 10 years |  |
SAR II [Member] |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |
Expected term |  |  |  | 7 years 3 months |  |
Risk-free interest rate |  |  |  | 1.76% |  |
Dividend yield |  |  |  | $ 0 |  |
Anticipated volatility factor and zero dividend yield |  |  |  | 50.00% |  |
Fair value of SAR granted |  |  |  | $ 12.96 |  |
Compensation expenses |  |  |  | $ 37,000 | $ 0 | $ 0
Total unrecognized compensation expense |  |  | $ 740,000 | $ 740,000 |  |
Market value of the Company's common stock |  |  | $ 24.41 | $ 24.41 |  |
Exercise price |  |  | $ 24.41 | $ 24.41 |  |
Expected period of recognition of cost |  |  |  | 6 years |  |

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