Derivative Financial Instruments (Details) (USD $)	12 Months Ended
	Dec. 31, 2014 swaps	Dec. 31, 2013	Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Number of derivative instruments obtained	6
Derivative maturity date	Jan. 01, 2019
Amount of borrowings outstanding	$ 225,000,000
Interest rate under derivative instruments	1.678%
Cross-default minimum threshold	10,000,000
Expected increase to interest expense	3,100,000
Derivatives designated as cash flow hedges in prepaid expenses and other assets [Abstract]
Interest rate swaps	0	301,000
Derivatives designated as cash flow hedges in accounts payable, accrued expenses and other liabilities [Abstract]
Interest rate swaps	2,412,000	510,000
Amount of unrealized gains/(losses) recognized in AOCL on derivatives (effective portion) [Abstract]
Interest rate swaps	(5,662,000)	5,778,000	(10,358,000)
Amount of losses reclassified out of AOCL into contractual interest expense (effective portion) [Abstract]
Interest rate swaps	$ 3,777,000	$ 3,370,000	$ 3,053,000