Derivatives and Hedging Activities (Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance) (Details) (Cash Flow Hedging, Interest Rate Swap, USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
Amount of loss recognized in accumulated other comprehensive loss from interest rate derivatives (effective portion)	$ (656)	$ (35)
Amount of income (loss) recognized in gain (loss) on derivative instruments (ineffective portion and amount excluded from effectiveness testing)	0	0
Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Amount of loss reclassified from accumulated other comprehensive loss into income as interest expense (effective portion)	$ (530)	$ (213)