Debt (Schedule of Interest Rate Derivatives) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($)
Interest Rate Swap, Date Entered, May 2012 [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.29%
Debt Instrument, Description of Variable Rate Basis	1-month LIBOR
Derivative, Notional Amount	$ 40,000
Interest Rate Swap, Date Entered, June 2013 [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.86%
Debt Instrument, Description of Variable Rate Basis	1-month LIBOR
Derivative, Notional Amount	$ 80,000
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (227)
Interest Rate Swap, Date Entered, March 2014 [Member]
Derivative [Line Items]
Derivative, Fixed Interest Rate	3.91%
Debt Instrument, Description of Variable Rate Basis	1-month LIBOR
Derivative, Notional Amount	$ 130,000
Interest Rate Cash Flow Hedge Liability at Fair Value	$ (520)