Related Party Transactions (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Directors, executive officers and their related parties
Related Party Transactions
Subordinated notes	$ 10,000,000		$ 10,000,000
Interest paid on subordinated notes	0	0
Interest accrued and unpaid on loans to directors	2,400,000
Directors, executive officers and their related parties | Bank
Changes in the total amounts of outstanding loans, advances under lines of credit as well as repayments
Outstanding at beginning of the year	33,296,000	87,442,000
New loans and advances	12,188,000	9,870,000
Repayments / reductions	(10,853,000)	(10,814,000)
Other	(256,000)
Outstanding at end of period	34,375,000	86,498,000
Related Party Transactions
Amount of loan to directors, executive officers and their related parties which are not performing in accordance with the terms of the loan agreements	190,000
Amount of loan outstanding under a commercial line of credit	34,375,000	86,498,000
Deposits from directors, executive officers and their related parties	57,000,000		66,700,000
Interest paid	35,000	81,000
Various companies of related parties
Related Party Transactions
Payments for services to related party	1,200,000	217,000
Director
Changes in the total amounts of outstanding loans, advances under lines of credit as well as repayments
Outstanding at end of period	6,600,000
Related Party Transactions
Amount of loan outstanding under a commercial line of credit	6,600,000
Amount of participation interest sold	5,200,000
Amount of participation interest outstanding	$ 2,600,000
Director | Bank
Related Party Transactions
Annual servicing fee received (as a percent)	0.25%