Commitments and Contingencies (Details) (USD $) In Thousands, unless otherwise specified	1 Months Ended							9 Months Ended
	Feb. 28, 2011 Directors	Sep. 30, 2013	Dec. 31, 2012	Sep. 30, 2013 Commitments to Extend Credit	Dec. 31, 2012 Commitments to Extend Credit	Sep. 30, 2013 Standby Letters of Credit	Dec. 31, 2012 Standby Letters of Credit	Sep. 30, 2013 Recourse Obligation on Mortgage Loans Sold	Dec. 31, 2012 Recourse Obligation on Mortgage Loans Sold	Sep. 30, 2013 Obligation to Repurchase Receivables Sold	Dec. 31, 2012 Obligation to Repurchase Receivables Sold
Guarantor Obligations [Line Items]
Unused commitments				$ 5,788,492	$ 5,467,998
Guarantor obligations amount						56,941	63,085	200,379	205,888
Reserve for estimated losses arising from repurchase of loans										3,641	4,065
Recourse Period, Maximum1								120 days
Number of directors in complaint	5
Payable to FDIC for loss share agreements		$ 107,419	$ 101,641