Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Guarantor Obligations [Line Items]
Amortization Method Qualified Affordable Housing Project Investments	$ 109,800	$ 85,600
FDIC loss share receivable	4,172	4,054	$ 28,701	$ 93,397
FDIC shared-loss payable	97,008	126,453
Federal Home Loan Bank, Advances, Maturities Summary, Fixed Rate	200,000
Commitments to Extend Credit
Guarantor Obligations [Line Items]
Unused Commitments to Extend Credit	8,810,000	7,950,000
Affordable Housing Program Obligation	57,100	41,800
Standby Letters of Credit
Guarantor Obligations [Line Items]
Guarantor obligations amount	$ 83,750	77,939
Recourse Obligation on Mortgage Loans Sold
Guarantor Obligations [Line Items]
Recourse Period, Maximum1	180 days
Obligation to Repurchase Receivables Sold
Guarantor Obligations [Line Items]
Reserve for estimated losses arising from repurchase of loans	$ 3,000	$ 3,000
Each Individual Advance [Member]
Guarantor Obligations [Line Items]
Federal Home Loan Bank, Advances, Maturities Summary, Fixed Rate	$ 100,000