Allowance for Loan Losses - Additional Information (Detail)	3 Months Ended		6 Months Ended
	Jun. 30, 2015 USD ($) Property	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) Property	Jun. 30, 2014 USD ($)	Apr. 30, 2015 USD ($)	Dec. 31, 2014 USD ($) Property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Period of nonperforming loans			90 days
Non-accruing loans excluded from impaired loan	$ 591,000		$ 591,000			$ 663,000
Non-accruing loans accrued interest	$ 4,000	$ 6,000	$ 8,000	$ 13,000
No. of Properties | Property	19		19			27
Other Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Properties marketed for sale					$ 398,000
No. of Properties | Property	2		2
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Residential properties collateralized with loan | Property	1
Residential mortgage loan amount	$ 28,000		$ 28,000
Residential | Other Assets
Accounts, Notes, Loans and Financing Receivable [Line Items]
Properties marketed for sale	724,000		724,000			$ 771,000
Residential First Mortgages
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance in order to assign a risk rating grade	1,000,000		1,000,000
Consumer and Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Minimum balance in order to assign a risk rating grade	$ 250,000		$ 250,000