Loans and Allowance for Credit Losses Narrative (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Financing Receivable, Allowance for Credit Losses [Line Items]
Provision for loan losses gross	$ 200,000	$ 50,000
Provision for credit losses	2,500,000	15,000,000
Percentage of unallocated allowance	6.00%	10.00%
Recorded Investment, Loans Sold		9,880,000
Charge-offs Upon Sale, Loan Sold		5,240,000
Minimum balance of loans evaluated individually for impairment	1,000,000
Impaired loans with principal balances approximately in percentage	79.00%	73.00%
Impaired loans balances, real estate as collateral	1,000,000
Loan to value ratio in the Corporation's policy	70.00%
Recorded investment, with no related allowance	67,642,000		61,893,000
TDR additional commitments to lend	$ 5,200,000		$ 9,600,000
Delinquent [Member] | Minimum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Days past due	31
Delinquent [Member] | Maximum [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Days past due	89
Non-performing [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Days past due	90