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Amount of operating dividend income on securities.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Measure of dispersion, in percentage terms (for instance, the standard deviation or variance), for a given stock price.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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2012 Incentive Compensation Plan - Additional Information (Detail) - USD ($)				3 Months Ended		6 Months Ended
	Jul. 06, 2015	Jun. 06, 2012	Apr. 29, 2011	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted under SAR Award Agreement		543,872
Common stock, market value per share				$ 22.07		$ 22.07
Valuation dates of common stock under SAR award agreement, description						Commenced after the SAR Grant Date and prior to the expiration date
SAR award expiration period from grant date						10 years
Expected term						6 years
Risk-free interest rate						0.92%
Dividend yield						$ 0
Anticipated volatility factor and zero dividend yield			50.00%			55.00%
Discount on valuation of trading activity				15.00%		15.00%
Service period						1 year 9 months 11 days
Expenses for the SAR granted				$ 37,000	$ 105,000	$ 86,000	$ 228,000
Total unrecognized compensation expense				$ 333,000		333,000
Total expected expense from initial grant						$ 2,133,000
Expected period of recognition of cost						4 years
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.
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term to exceed public equivalent value over aggregate exercise price						$ 22.07
SAR [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value of SAR granted						$ 3.31
SAR [Member] \| Chief Operating Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted to employees		543,872
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				801,060		801,060
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted to employees						185,993
Fair value of SAR granted						$ 0
Unvested portion of the company's common stock				137,170		137,170		154,251
Number of vesting shares						17,081
Expected period of recognition of cost						7 years
Compensation expenses				$ 235,000	$ 237,000	$ 491,000	$ 435,000
Restricted Stock [Member] \| 2012 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation expense				$ 5,511,000		$ 5,511,000
Restricted Stock [Member] \| Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period for restricted stock						10 years
SAR Award Agreement Amended [Member] \| Subsequent Event [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 Award Agreement Amended [Member] \| Subsequent Event [Member] \| Tranche One [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting shares	100,000
SAR Award Agreement Amended [Member] \| Subsequent Event [Member] \| Tranche Two [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of vesting shares	81,290
SAR Award Agreement Amended [Member] \| Subsequent Event [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 Award Agreement Amended [Member] \| Subsequent Event [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 Award Agreement Amended [Member] \| Subsequent Event [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 Award Agreement Amended [Member] \| Subsequent Event [Member] \| Deferred Bonus Granted in 2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of annual bonus	$ 250,000