Derivative Financial Instruments - Effect of Derivative Financial Instruments on Income Statement (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Not Designated as Hedging Instrument | Interest rate contracts | Other income
Derivative [Line Items]
Amount of Gain (Loss) Recognized Income on Derivative	$ 19	$ 66
Designated as Hedging Instrument | Cash Flow Hedging | Interest Expense
Derivative [Line Items]
Amount of Gain (Loss) Reclassified from Other Comprehensive Income into Income (Effective Portion)	(344)	(188)
Designated as Hedging Instrument | Interest rate contracts | Cash Flow Hedging
Derivative [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income on Derivative (Effective Portion)	$ (1,266)	$ 297