Summary of Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($) Segment	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($)
Summary Of Significant Accounting Policies [Line Items]
Federal Deposit Insurance Corporation protection limits	$ 250,000
Un-amortized franchise fees	457,128			$ 471,996
Amortization expense	14,869	$ 17,032
Deferred income taxes	4,846,500			5,131,179
Deferred tax assets related to net operating losses	$ 4,200,000			4,400,000
Minimum percentage of likelihood of realization of deferred tax assets	50.00%
Deferred tax assets valuation allowance	$ 0
Uncertain tax positions	0			$ 0
Compensation cost recognized	166,451	171,523
Advertising cost	97,668	98,313
Gain on involuntary conversion of assets	161,334	$ 870,741
Number of reportable segment | Segment		1
ESOP [Member]
Summary Of Significant Accounting Policies [Line Items]
Compensation cost recognized	$ 66,093	$ 60,170
Director [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares issued but not vested | shares	13,000
Shares award vesting date	Dec. 31, 2019
2013 Plan [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares issued under plan | shares	176,350
Performance-based stock awards granted | shares	0
Compensation cost recognized	$ 100,358	111,352
2013 Plan [Member] | Director [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares issued under plan | shares	33,000
2013 Plan [Member] | Executives and Employees [Member]
Summary Of Significant Accounting Policies [Line Items]
Shares issued under plan | shares	143,350
2013 Plan [Member] | One Employee [Member]
Summary Of Significant Accounting Policies [Line Items]
Stock award vesting period	4 years
Shares issued but not vested | shares	20,000
Other Operating Departments [Member]
Summary Of Significant Accounting Policies [Line Items]
Lease revenue	$ 400,000	$ 500,000
ASU 2016-02 [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating Lease, right of use assets, net	6,200,000
Operating lease obligations	$ 3,800,000
ASU 2018-11 [Member]
Summary Of Significant Accounting Policies [Line Items]
Operating Lease, right of use assets, net			$ 6,300,000
Operating lease obligations			$ 3,800,000
Maximum [Member] | 2013 Plan [Member] | Employees [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted, unrestricted and performance stock awards permitted to grant to employees and directors | shares	350,000
Maximum [Member] | 2013 Plan [Member] | Director [Member]
Summary Of Significant Accounting Policies [Line Items]
Restricted, unrestricted and performance stock awards permitted to grant to employees and directors | shares	750,000
Buildings and Building Improvements [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	7 years
Buildings and Building Improvements [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	39 years
Furniture, Fixtures and Equipment [Member] | Minimum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	5 years
Furniture, Fixtures and Equipment [Member] | Maximum [Member]
Summary Of Significant Accounting Policies [Line Items]
Estimated useful lives of the assets	10 years