Goodwill And Intangible Assets (Summary Of Intangible Assets Other Than Goodwill) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 24,323		$ 37,797
Less: Accumulated amortization	(20,629)		(30,428)
Net intangible assets other than goodwill	3,694	$ 3,827	7,369
Beneficial Leases [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	15,069		28,592
Less: Accumulated amortization	(14,260)		(24,145)
Net intangible assets other than goodwill	809		4,447
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	7,255		7,254
Less: Accumulated amortization	(5,269)		(5,207)
Net intangible assets other than goodwill	1,986		2,047
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	1,999		1,951
Less: Accumulated amortization	(1,100)		(1,076)
Net intangible assets other than goodwill	$ 899		$ 875