Goodwill And Intangible Assets (Narrative) (Details)	3 Months Ended
	Mar. 31, 2018
Beneficial Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful life	30 years
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful life	45 years
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Intangible assets estimated useful life	30 years