Trust Preferred Securities (Details) (USD $)	0 Months Ended	12 Months Ended
	Dec. 15, 2004	Dec. 31, 2012 item	Dec. 31, 2011	Dec. 31, 2010	Dec. 15, 2012 item
Subordinated Borrowing [Line Items]
Private placement, trust preferred securities, aggregate amount	$ 20,000,000
Trust preferred securities		20,619,000	20,619,000
LIBOR plus percentage		1.95%
Number of interest rate swap arrangements		1			2
Maturity date		Apr. 01, 2015
Interest expense on trust preferred securities		1,180,000	1,190,000	1,190,000
Trust Preferred Securities [Member]
Subordinated Borrowing [Line Items]
Maturity date		Dec. 31, 2034
Fixed Interest Rate Initial 3 Years [Member]
Subordinated Borrowing [Line Items]
Amount of hedged item		10,000,000
Fixed interest rate		6.50%
Fixed rate, number of years		3
Fixed Interest Rate Subsequent 7 Years [Member]
Subordinated Borrowing [Line Items]
Amount of hedged item		$ 10,000,000
Fixed interest rate		5.23%