Commitments and Contingent Liabilities (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Future minimum lease commitments under non-cancelable operating leases
2014	$ 1,594,000
2015	1,255,000
2016	1,336,000
2017	1,315,000
2018	875,000
Thereafter	2,253,000
Rent expense, net of sublease income	1,693,000	1,795,000	1,804,000
Commitments to extend credit and standby letters of credit
Commitments and contingent liabilities
The amount of commitments made by the entity	469,500,000	401,100,000
Standby letters of credit
Commitments and contingent liabilities
The amount of commitments made by the entity	15,200,000	14,800,000
Standby letters of credit | Minimum
Commitments and contingent liabilities
Term of the guarantee agreements	1 year
Standby letters of credit | Maximum
Commitments and contingent liabilities
Term of the guarantee agreements	2 years
Agreements to guarantee performance of customers contracts
Future minimum lease commitments under non-cancelable operating leases
Expected payment required in an event of default on all contracts	$ 2,500,000
Agreements to guarantee performance of customers contracts | Minimum
Commitments and contingent liabilities
Term of the guarantee agreements	3 months
Agreements to guarantee performance of customers contracts | Maximum
Commitments and contingent liabilities
Term of the guarantee agreements	12 months