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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Stock-based Compensation - Summary of Information Related to Stock Option Plan (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cash received from stock option exercises			$ 514,050	$ 329,550
2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised	$ 234,410		486,860	166,950
Cash received from stock option exercises	118,750		195,000	101,550
2010 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised			876,050	370,000
Cash received from stock option exercises			319,050	228,000
Tax benefit realized from option exercised			159,525	121,609
2010 Plan \| Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Tax benefit realized from awards vested	$ 272,133	$ 123,406	$ 285,289	$ 211,753