Assets & Liability Derivative Positions & the Potential Effect of Netting Arrangements - Current Quarter (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Offsetting Liabilities [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 18,860	$ 16,697
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	18,860	16,697
Derivative, Collateral, Obligation to Return Securities	1,260	2,823
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	17,599	13,874
Derivative Liability, Fair Value, Gross Liability	227,956	225,648
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	227,956	225,648
Derivative, Collateral, Right to Reclaim Securities	1,260	2,823
Derivative, Collateral, Right to Reclaim Cash	220,184	219,026
Derivative Liability, Fair Value, Amount Offset Against Collateral	6,511	3,799
Interest rate swaps
Offsetting Liabilities [Line Items]
Derivative Asset, Fair Value, Gross Asset	0	0
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	0	0
Derivative, Collateral, Obligation to Return Securities	0	0
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	0	0
Derivative Liability, Fair Value, Gross Liability	5,923	9,630
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	5,923	9,630
Derivative, Collateral, Right to Reclaim Securities	0	0
Derivative, Collateral, Right to Reclaim Cash	5,923	9,630
Derivative Liability, Fair Value, Amount Offset Against Collateral	0	0
Loan level derivatives
Offsetting Liabilities [Line Items]
Derivative Asset, Fair Value, Gross Asset	14,820	16,301
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	14,820	16,301
Derivative, Collateral, Obligation to Return Securities	1,260	2,823
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	13,560	13,478
Derivative Liability, Fair Value, Gross Liability	14,829	16,340
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	14,829	16,340
Derivative, Collateral, Right to Reclaim Securities	1,260	2,823
Derivative, Collateral, Right to Reclaim Cash	12,308	10,108
Derivative Liability, Fair Value, Amount Offset Against Collateral	1,260	3,409
Customer foreign exchange contracts
Offsetting Liabilities [Line Items]
Derivative Asset, Fair Value, Gross Asset	4,040	396
Derivative Asset, Collateral, Obligation to Return Cash, Offset	0	0
Derivative Asset	4,040	396
Derivative, Collateral, Obligation to Return Securities	0	0
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative Asset, Fair Value, Amount Offset Against Collateral	4,040	396
Derivative Liability, Fair Value, Gross Liability	4,012	390
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	4,012	390
Derivative, Collateral, Right to Reclaim Securities	0	0
Derivative, Collateral, Right to Reclaim Cash	0	0
Derivative Liability, Fair Value, Amount Offset Against Collateral	4,012	390
Customer repurchase agreements
Offsetting Liabilities [Line Items]
Derivative Liability, Fair Value, Gross Liability		149,288
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	153,192	149,288
Derivative, Collateral, Right to Reclaim Securities	0	0
Derivative, Collateral, Right to Reclaim Cash	151,953	149,288
Derivative Liability, Fair Value, Amount Offset Against Collateral	1,239	0
Wholesale repurchase agreements
Offsetting Liabilities [Line Items]
Derivative Liability, Fair Value, Gross Liability	50,000	50,000
Derivative Liability, Collateral, Right to Reclaim Cash, Offset	0	0
Derivative Liability	50,000	50,000
Derivative, Collateral, Right to Reclaim Securities	0	0
Derivative, Collateral, Right to Reclaim Cash	50,000	50,000
Derivative Liability, Fair Value, Amount Offset Against Collateral	$ 0	$ 0