Loans (Narrative) (Detail) - USD ($)	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial real estate loans	$ 139,812,000	$ 117,627,000
Commercial loans	46,372,000	37,536,000
Minimum principal balance of loans for quarterly rating review	$ 500,000
Minimum number of days consumer loans are delinquent for quarterly rating review	90 days
Minimum number of days commercial loans are delinquent for quarterly rating review	60 days
Syndicated Loan Facility [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial loans	$ 3,078,000	3,704,000
United States Department of Agriculture Rural Development [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Commercial real estate loans	$ 12,364,000	$ 12,612,000