Derivative Instruments Designated at Hedging Instruments (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013		Sep. 30, 2013
Derivatives designated in hedge relationships
Derivative Asset, Fair Value	$ 43,097	$ 47,902		$ 53,839
Derivative Liability, Fair Value	49,280	58,201		65,506
Interest rate swaps | Designated as Hedging Instrument
Derivatives 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	100,490	126,637		133,159
Derivative Liability, Fair Value	$ 7,584	$ 11,574		$ 13,289

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