Derivative Instruments and Hedging Activities (Details Textual) $ in Millions	6 Months Ended
	Jun. 30, 2015 USD ($)
Interest Rate Cap One [Member]
Derivatives, Fair Value [Line Items]
Derivative, Maturity Date	Jan. 22, 2016
Derivative Liability, Notional Amount	$ 100
Derivative, Cap Interest Rate	2.50%
Interest Rate Cap [Member]
Derivatives, Fair Value [Line Items]
Derivative, Maturity Date	Jul. 22, 2015
Derivative Liability, Notional Amount	$ 275
Derivative, Cap Interest Rate	2.50%