Derivative Instruments (Schedule of Fair Values of Derivative Instruments) (Details) (USD $) In Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2011		Sep. 30, 2010	Sep. 30, 2011		Sep. 30, 2010	Dec. 31, 2010
Derivative instruments	$ 22,277	[1]		$ 22,277	[1]		$ 18,823	[1]
Total liability derivatives	(23,484)	[1]		(23,484)	[1]		(19,584)
Interest Rate Swaps [Member] | Derivatives Designated As Hedging Instruments [Member]
Other liabilities	(1,190)			(1,190)			(1,159)
Interest Rate Swaps [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	20,425			20,425			17,712
Other liabilities	(20,646)			(20,646)			(17,799)
Interest Rate Caps [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	14			14			84
Other liabilities	(14)			(14)			(84)
Credit Risk Participation Agreements [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	9			9
Other liabilities	(152)			(152)			(130)
Foreign Exchange (Forward Contracts) [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	1,508			1,508			492
Other liabilities	(1,400)			(1,400)			(359)
Foreign Exchange (Option Contracts) [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	2			2
Other liabilities	(2)			(2)
Mortgage Loan Commitments [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	286			286			101
Other liabilities	(1)			(1)			(30)
Mortgage Loan Forward Sale Contracts [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Other assets	33			33			434
Other liabilities	(79)			(79)			(23)
Derivatives Designated As Hedging Instruments [Member]
Other liabilities	(1,190)			(1,190)			(1,159)
Derivatives Not Designated As Hedging Instruments [Member]
Other assets	22,277			22,277			18,823
Other liabilities	(22,294)			(22,294)			(18,425)
Total derivatives not designated as hedging instruments	$ 180		$ 31	$ 521		$ 828

[1] The fair value of each class of derivative is shown in Note 10.