Fair Value of Financial Instruments (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Interest Rate Swap - Fair Value, Measurements, Recurring - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	$ 8,630	$ 4,321
Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	0	0
Significant Other Observable Inputs (Level 2)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	8,630	4,321
Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	$ 0	$ 0