Derivatives and Hedging Activities (Details) (USD $)	6 Months Ended	1 Months Ended					6 Months Ended
	Jun. 30, 2014	Jan. 31, 2012 Interest Rate Swap [Member]	Jun. 30, 2014 Designated as Hedging Instrument [Member] Interest Rate Swap [Member] Other Assets [Member]	Dec. 31, 2013 Designated as Hedging Instrument [Member] Interest Rate Swap [Member] Other Assets [Member]	Jun. 30, 2014 Designated as Hedging Instrument [Member] Interest Rate Swap [Member] Accounts Payable And Other Liabilities [Member]	Jun. 30, 2014 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Swap [Member] Financial_Instrument	Jun. 30, 2014 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Swap [Member] Interest Expense [Member]	Jun. 30, 2013 Designated as Hedging Instrument [Member] Cash Flow Hedging [Member] Interest Rate Swap [Member] Interest Expense [Member]
Derivative [Line Items]
Notional amount						$ 505,000,000
Settlement amount		3,539,000
Amount of loss reclassified from accumulated OCI into income (effective portion)		1,837,000					2,681,000	1,285,000
Expected amount of derivative related interest to be reclassified to interest expense over the next 12 months	5,477,000
Number of derivative instruments held						10
Derivative asset			894,000	4,439,000
Derivative Liability					(960,000)
Amount of gain (loss) recognized in OCI on derivatives (effective portion)							$ (7,186,000)	$ 8,851,000