Trust Preferred Securities - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended
	May 31, 2007	Dec. 31, 2013	Dec. 31, 2012
Trust Preferred Securities [Line Items]
Accrued interest payable		$ 789,000	$ 882,000
Maturity date of subordinate notes		Jun. 15, 2037
Balance of the subordinated notes payable		16,238,000	16,238,000
Trust I [Member]
Trust Preferred Securities [Line Items]
Preferred securities sold to outside investors	10,000,000
Floating interest rate period	three-month LIBOR
LIBOR basis points	1.48%
Effective interest rate		1.72%
Accrued interest payable		6,000	5,000
Trust II [Member]
Trust Preferred Securities [Line Items]
Floating interest rate period	three-month LIBOR
LIBOR basis points	1.48%
Fixed interest rate of Trust II	6.64%
Effective interest rate		6.64%
Accrued interest payable		22,000	0
Balance of the subordinated notes payable		$ 8,119,000