Premises and Equipment - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Depreciation and amortization	$ 422,478	$ 505,520	$ 625,040
Noncancelable lease arrangements
Property Plant And Equipment [Line Items]
Lease extension maturity period	2028
Rent expenses related to leases	$ 1,016,000	$ 1,018,000	$ 994,000