Investments In Direct Financing Leases (Summary Of Carrying Amounts Of Investment In Direct Financing Lease, Net) (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	May 21, 2015
Capital Leases, Net Investment in Direct Financing Leases [Abstract]
Proceeds from Sale of Lease Receivables		$ 0	$ 20,951	$ 4,741
Total minimum lease payments receivable		112,411	215,753
Estimated unguaranteed residual value of leased assets		47,000	85,247
Less deferred income	[1]	(101,508)	(198,302)
Investment in direct financing leases, net		57,903	102,698		$ 4,700
Initial direct costs		$ 800	$ 1,300

[1] Deferred income is net of $0.8 million and $1.3 million of initial direct costs at December 31, 2017 and 2016, respectively.