Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Guarantor Obligations [Line Items]
Amortization Method Qualified Affordable Housing Project Investments	$ 85,600	$ 57,100
FDIC loss share receivable	4,054	28,701	$ 93,397	$ 270,192
FDIC loss share payable	126,453	116,535
Commitments to Extend Credit
Guarantor Obligations [Line Items]
Unused Commitments to Extend Credit	7,950,000	7,190,000
Affordable Housing Program Obligation	41,800	16,800
Standby Letters of Credit
Guarantor Obligations [Line Items]
Guarantor obligations amount	$ 77,939	77,374
Recourse Obligation on Mortgage Loans Sold
Guarantor Obligations [Line Items]
Recourse Period, Maximum1	120 days
Obligation to Repurchase Receivables Sold
Guarantor Obligations [Line Items]
Reserve for estimated losses arising from repurchase of loans	$ 3,000	$ 3,203