Stock Options and Restricted Stock - Additional Information (Detail)	3 Months Ended
Mar. 31, 2019 USD ($) Incentive_Plan shares	Mar. 31, 2018 USD ($) shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of equity incentive plans \| Incentive_Plan	3
Stock options exercised, Shares \| shares	5,000	15,000
Proceeds from stock option exercises	$ 20,000	$ 68,000
Share-based compensation expense	$ 600,000	$ 17,800

Number of share options (or share units) exercised during the current period.

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Balance Type:	na
Period Type:	duration