Stock Compensation - Additional Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of nonqualified options or restricted stock for key employees and independent director	500,000
Description of award terms	For key employees, the plan vesting is one-fourth of the granted options or restricted stock per year beginning one year after the grant date, with 100% vested on the fourth anniversary of the grant date. For independent directors, the vesting schedule is one-third of the granted options or restricted stock per year beginning one year after the grant date, with 100% vested on the third anniversary of the grant date.
Unrecognized compensation cost related to nonvested stock options granted under this plan	$ 0
Stock options, granted	0	0
Compensation expense restricted stock awards	$ 240,000	$ 157,000
Key Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Starting period of vesting of stock based award	1 year
Aggregate percentage of stock based awards to be matured	100.00%
Stock incentive plan, vesting per year	25.00%
Award vesting period	4 years
Independent Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Starting period of vesting of stock based award	1 year
Aggregate percentage of stock based awards to be matured	100.00%
Stock incentive plan, vesting per year	33.33%
Award vesting period	3 years
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested restricted stock	$ 1,600,000

Aggregate percentage of stock based awards to me matured.

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- Definition

Number of nonqualified options or restricted stock for key employees and independent director.

+ References

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- Definition

Starting period of vesting of share based award.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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- Definition

The noncash expense that represents the cost of restricted stock or unit distributed to employees as compensation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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