Fair Value Measurements (Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Term deposits	$ 17	$ 16
Interest rate swaps	222	0
Total assets	239	16
Interest rate swaps	0	334
Total liabilities	0	334
Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Term deposits	17	16
Interest rate swaps	0	0
Total assets	17	16
Interest rate swaps	0	0
Total liabilities	0	0
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Term deposits	0	0
Interest rate swaps	222	0
Total assets	222	0
Interest rate swaps	0	334
Total liabilities	0	334
Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Term deposits	0	0
Interest rate swaps	0	0
Total assets	0	0
Interest rate swaps	0	0
Total liabilities	$ 0	$ 0