Derivatives and Hedging Activities (Not Designated as Hedging Instruments, Notional Values, Contractual Amounts and Fair Value) (Details) - USD ($) $ in Thousands		Jun. 30, 2015	Dec. 31, 2014		Jun. 30, 2014
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		$ 48,073	$ 55,197		$ 50,550
Derivative Liability, Fair Value		51,497	55,439		57,544
Not Designated as Hedging Instrument
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		1,823,511	1,807,942		1,828,587
Derivative Asset, Fair Value	[1]	46,920	49,941		50,550
Derivative Liability, Notional/Contract Amount		1,847,653	1,821,674		1,783,908
Derivative Liability, Fair Value		46,393	48,756		48,555
Not Designated as Hedging Instrument | Interest rate swaps
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		1,726,600	1,673,012		1,618,463
Derivative Asset, Fair Value		46,216	48,366	[1]	47,952	[1]
Derivative Liability, Notional/Contract Amount		1,726,600	1,673,012		1,618,463
Derivative Liability, Fair Value		46,216	48,366		47,952
Not Designated as Hedging Instrument | Mortgage loan commitments
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		52,024	102,523		169,232
Derivative Asset, Fair Value		342	1,408	[1]	2,491	[1]
Derivative Liability, Notional/Contract Amount		0	0		0
Derivative Liability, Fair Value		0	0		0
Not Designated as Hedging Instrument | Forward sales contracts
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		15,200	0		0
Derivative Asset, Fair Value		106	0	[1]	0	[1]
Derivative Liability, Notional/Contract Amount		0	47,657		80,161
Derivative Liability, Fair Value		0	272		545
Not Designated as Hedging Instrument | Credit Risk Contract
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		0	10,001		15,269
Derivative Asset, Fair Value	[1]	0	0		0
Derivative Liability, Notional/Contract Amount		73,512	69,227		52,319
Derivative Liability, Fair Value			0		10
Not Designated as Hedging Instrument | Equity Swap
Derivatives not designated in hedge relationships
Derivative Liability, Fair Value		0
Not Designated as Hedging Instrument | Foreign Exchange
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		29,687	22,406		25,623
Derivative Asset, Fair Value		256	167	[1]	107	[1]
Derivative Liability, Notional/Contract Amount		15,823	6,580		7,568
Derivative Liability, Fair Value		177	118		48
Not Designated as Hedging Instrument | Other Contract
Derivatives not designated in hedge relationships
Derivative Asset, Notional/Contract Amount		0	0		0
Derivative Asset, Fair Value		0	0	[1]	0	[1]
Derivative Liability, Notional/Contract Amount		31,718	25,198		25,397
Derivative Liability, Fair Value			0		0
Level 2
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		48,073	55,197		50,550
Derivative Liability, Fair Value		51,497	55,439		57,544
Level 2 | Not Designated as Hedging Instrument | Interest rate swaps
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		46,216	48,366		47,952
Derivative Liability, Fair Value		46,216	48,366		47,952
Level 2 | Not Designated as Hedging Instrument | Mortgage loan commitments
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		342	1,408		2,491
Level 2 | Not Designated as Hedging Instrument | Forward sales contracts
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		106	0		0
Derivative Liability, Fair Value		0	272		545
Level 2 | Not Designated as Hedging Instrument | Credit Risk Contract
Derivatives not designated in hedge relationships
Derivative Liability, Fair Value					10
Level 2 | Not Designated as Hedging Instrument | Foreign Exchange
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		256	167		107
Derivative Liability, Fair Value		177	118		48
Level 3
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		0	0		0
Derivative Liability, Fair Value		0	0		0
Level 3 | Not Designated as Hedging Instrument | Interest rate swaps
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		0	0		0
Derivative Liability, Fair Value		0	0		0
Level 3 | Not Designated as Hedging Instrument | Mortgage loan commitments
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		0	0		0
Level 3 | Not Designated as Hedging Instrument | Forward sales contracts
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		0	0		0
Derivative Liability, Fair Value		0	0		0
Level 3 | Not Designated as Hedging Instrument | Credit Risk Contract
Derivatives not designated in hedge relationships
Derivative Liability, Fair Value					0
Level 3 | Not Designated as Hedging Instrument | Equity Swap
Derivatives not designated in hedge relationships
Derivative Liability, Fair Value		0
Level 3 | Not Designated as Hedging Instrument | Foreign Exchange
Derivatives not designated in hedge relationships
Derivative Asset, Fair Value		0	0		0
Derivative Liability, Fair Value		$ 0	$ 0		$ 0

[1] (1) Included in "Other assets" on the Consolidated Balance Sheets(2) Included in "Other liabilities" on the Consolidated Balance Sheets