Derivative Financial Instruments (Gains (losses) recognized on derivatives (cash flow hedges)) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Interest Expense | Interest Rate Swap 1
Trading Activity, Gains and Losses, Net [Line Items]
Effective Portion, Recognized in OCI, Amount of Gain (Loss)	$ 203	$ (58)
Effective Portion, Reclassified from AOCI into Income, Amount of Gain (Loss)	(210)	(226)
Interest Expense | Interest Rate Swap 2
Trading Activity, Gains and Losses, Net [Line Items]
Effective Portion, Recognized in OCI, Amount of Gain (Loss)	419	189
Effective Portion, Reclassified from AOCI into Income, Amount of Gain (Loss)	(436)	(397)
Interest Expense | Interest Rate Swap 3
Trading Activity, Gains and Losses, Net [Line Items]
Effective Portion, Recognized in OCI, Amount of Gain (Loss)	548	(262)
Effective Portion, Reclassified from AOCI into Income, Amount of Gain (Loss)	(446)	(421)
Interest Expense | Interest Rate Swap 4
Trading Activity, Gains and Losses, Net [Line Items]
Effective Portion, Recognized in OCI, Amount of Gain (Loss)	1,115	(606)
Effective Portion, Reclassified from AOCI into Income, Amount of Gain (Loss)	(460)	(442)
Other Income | Interest Rate Swap 1
Trading Activity, Gains and Losses, Net [Line Items]
Ineffective Portion, Recognized in Income on Derivatives, Amount of Gain (Loss)	0	0
Other Income | Interest Rate Swap 2
Trading Activity, Gains and Losses, Net [Line Items]
Ineffective Portion, Recognized in Income on Derivatives, Amount of Gain (Loss)	0	0
Other Income | Interest Rate Swap 3
Trading Activity, Gains and Losses, Net [Line Items]
Ineffective Portion, Recognized in Income on Derivatives, Amount of Gain (Loss)	0	0
Other Income | Interest Rate Swap 4
Trading Activity, Gains and Losses, Net [Line Items]
Ineffective Portion, Recognized in Income on Derivatives, Amount of Gain (Loss)	$ 0	$ 0