Derivative and Hedging Activities - Summary of Amounts Recorded in AOCL and Gain (Loss) Recorded in Operations when Reclassified out of AOCL or Recognized in Earnings (Details) (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Dec. 31, 2014
Dec. 31, 2013
Dec. 31, 2012
Interest Expense [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of Loss Reclassified from AOCL into Operations (Effective Portion) $ (1,315) $ (425) $ (3,646)
General and Administrative Expense [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of Loss Reclassified from AOCL into Operations (Effective Portion) 0 (22) (4,037)
Amount of Gain Recognized in Operations on Derivative (Ineffective Portion) 0 10 0
Cash Flow Hedging [Member] | Interest Rate Swap [Member]      
Derivative Instruments, Gain (Loss) [Line Items]      
Amount of Loss Recognized in AOCL on Derivative (Effective Portion) $ (1,760) $ (314) $ (902)