Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013 site	Dec. 31, 2012	Dec. 31, 2011
Loss Contingencies [Line Items]
Number of operating lease site	4
Rent expense	$ 430,000	$ 439,000	$ 465,000
Rent expense offset by rent income	15,000	81,000	58,000
Reserve for unfunded commitments, included in other liabilities	698,000	499,000
Additional provisions to reserve for unfunded commitments	200,000	0	0
Outstanding under the agreement	0	65,000,000
Real estate-related loans representing lease portfolio	70.00%	65.00%
Standby letters of credit [Member]
Loss Contingencies [Line Items]
Loss in connection with a standby letter of credit		73,000
Expiry of standby letter of credit within one year	1,600,000
Expiry of standby letter of credit thereafter	$ 3,000,000