Commitments and Contingencies (Sumamry Of Minimum Future Rental Revenue) (Details) $ in Thousands	Dec. 31, 2017 USD ($)
2018	$ 59,365
2019	59,320
2020	59,320
2021	59,320
2022	59,320
Thereafter	148,300
Total	444,945
Scenario, Plan [Member]
2018	22,727
2019	16,651
2020	14,273
2021	7,747
2022	4,958
Thereafter	247
Total	$ 66,603