Fair Value of Financial Instruments (Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) - Interest Rate Swap Agreements: - Fair Value, Measurements, Recurring $ in Thousands	Sep. 30, 2017 USD ($)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	$ 2,379
Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	0
Significant Other Observable Inputs (Level 2)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	2,379
Significant Unobservable Inputs (Level 3)
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Derivative financial instruments	$ 0