Business and Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2014 Subsidiary	Dec. 31, 2013	Dec. 31, 2012
Accounting Policies [Abstract]
Number of operating subsidiaries	2
Average amount of reserve requirement	$ 417,000	$ 407,000	$ 566,000
Percentage of partnership in other investment	99.00%
Federal Home Loan Bank Stock, par value	$ 100
Number of days required to review relative to collectability	90 days
Requirement of amount of loans secured by real estate to prepare appraisal	250,000
Validation period of Appraisals	12 months
Shares of common stock outstanding	5,123,186	5,128,889	5,136,918
Interest on deposits and borrowings	1,447,133	1,470,945	2,082,914
Income tax payments	320,000	810,000	835,000
Loans transferred to other real estate	1,345,170	4,536,710	2,575,520
Dividends paid			$ 513,692