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Income Taxes [Line Items]

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Publisher FASB

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Sum of operating profit and nonoperating income or expense before Income or Loss from equity method investments, income taxes, extraordinary items, and noncontrolling interest.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Description of material events or transactions not otherwise specified in the taxonomy pertaining to income taxes that would be relevant to the user of the financial statements.

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The amount of cash paid during the current period for taxes other than income taxes.

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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Income Taxes - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Jul. 31, 2015	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Income Taxes [Line Items]
Income before income taxes		$ 4,351,388	$ 3,243,249	$ 8,549,861	$ 8,641,354
Income tax provision		738,831	$ 417,827	$ 2,007,817	$ 1,538,829
Effective tax rate				23.50%	17.80%
Expected effective tax rate						24.23%
Subsequent Event
Income Taxes [Line Items]
Payments for excise tax	$ 140,626
Maximum
Income Taxes [Line Items]
Net operating loss and business tax credit carry forwards expiration date				At various dates through December 2032.
Available to Reduce Future Federal Income Taxes
Income Taxes [Line Items]
Net operating loss carry forwards		43,387,000		$ 43,387,000
Business tax credit carry forwards		$ 1,782,000		$ 1,782,000