Derivatives and Hedging Activity (Derivative Instruments not Designated as Hedging Instruments) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value	$ 58,107	$ 55,197
Derivative Liability, Fair Value, Gross Liability	52,745	55,439
Not Designated as Hedging Instrument
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	1,858,882	1,807,942
Derivative Asset, Fair Value	49,368	49,941
Derivative Liability, Notional/Contract Amount	1,956,287	1,821,674
Derivative Liability, Fair Value, Gross Liability	49,209	48,756
Not Designated as Hedging Instrument | Interest Rate Swap
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	1,824,576	1,673,012
Derivative Asset, Fair Value	48,920	48,366
Derivative Liability, Notional/Contract Amount	1,824,576	1,673,012
Derivative Liability, Fair Value, Gross Liability	48,920	48,366
Not Designated as Hedging Instrument | Mortgage Loan Commitments
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	20,635	102,523
Derivative Asset, Fair Value	149	1,408
Derivative Liability, Notional/Contract Amount	0	0
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument | Forward Contracts
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	0	0
Derivative Asset, Fair Value	0	0
Derivative Liability, Notional/Contract Amount	9,659	47,657
Derivative Liability, Fair Value, Gross Liability	5	272
Not Designated as Hedging Instrument | Credit contracts
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	0	10,001
Derivative Asset, Fair Value	0	0
Derivative Liability, Notional/Contract Amount	73,715	69,227
Derivative Liability, Fair Value, Gross Liability	0	0
Not Designated as Hedging Instrument | Foreign Exchange
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	13,671	22,406
Derivative Asset, Fair Value	299	167
Derivative Liability, Notional/Contract Amount	11,706	6,580
Derivative Liability, Fair Value, Gross Liability	284	118
Not Designated as Hedging Instrument | Equity swap
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount	0	0
Derivative Asset, Fair Value	0	0
Derivative Liability, Notional/Contract Amount	36,631	25,198
Derivative Liability, Fair Value, Gross Liability	$ 0	$ 0