Share-Based Compensation - Option Activity under Stock Option Plans (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Number of Shares
Outstanding, beginning of period (in shares)	31,706
Granted (in shares)	0	0
Exercised (in shares)	0	0
Outstanding, end of period (in shares)	31,706
Options exercisable end of period (in shares)	31,706
Weighted Average Exercise Price
Outstanding, beginning of period (in usd per share)	$ 7.76
Granted (in usd per share)	0
Exercised (in usd per share)	0
Outstanding, end of period (in usd per share)	7.76
Options exercisable at end of period (in usd per share)	$ 7.76
Weighted Average Remaining Contractual Term (in years)
Outstanding	10 days	17 days
Options exercisable	10 days
Aggregate Intrinsic Value
Outstanding	$ 96,811		$ 305,120
Options exercisable, end of period	$ 96,811