Derivatives and Hedging Activities (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) in OCI on derivatives (effective portion), net of tax	$ (411)	$ (929)	$ 350	$ (2,125)
Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gain (loss) in OCI on derivatives (effective portion), net of tax	(411)	(929)	350	(2,125)
Loss reclassified from OCI into interest expense (effective portion)	(1,464)	(1,370)	(4,322)	(4,008)
Loss recognized in income on derivatives (ineffective portion & amount excluded from effectiveness testing)
Derivatives not designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Changes in fair value of customer related positions	(26)	8	(81)	62
Other Income [Member] | Derivatives not designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Changes in fair value of customer related positions	1	12	27	85
Interest Expense [Member] | Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in income on derivatives (ineffective portion & amount excluded from effectiveness testing)
Other Expense [Member] | Derivatives designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Loss recognized in income on derivatives (ineffective portion & amount excluded from effectiveness testing)
Other Expense [Member] | Derivatives not designated as hedges [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Changes in fair value of customer related positions	$ (27)	$ (4)	$ (108)	$ (23)