Share-Based Compensation - Additional Information (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Compensation expense in stock compensation plans	$ 423,623	$ 521,689	$ 866,276	$ 1,000,000
Income tax benefit of stock compensation plans	88,961	109,555	181,918	218,897
Unrecognized compensation expense related to nonvested share-based compensation granted under the plan	1,500,000		$ 1,500,000
Weighted average period of unrecognized compensation expense			1 year 8 months 12 days
Cash from option exercises	795,182	$ 0	$ 795,182	478,650
Tax benefit for tax deductions related to option exercises	$ 15,962		$ 15,962	$ 18,803

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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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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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Amount of tax benefit from exercise of stock options granted under share-based compensation arrangement.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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