Leases (Book Value Of Assets Under Operating Leases From Owned Assets) (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Subject to or Available for Operating Lease [Line Items]
Gross balance	$ 550,028	$ 605,562
Accumulated depreciation	(243,418)	(252,437)
Operating property, net	306,610	353,125
Building And Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Gross balance	139,493	153,643
Accumulated depreciation	(22,815)	(26,107)
Operating property, net	$ 116,678	$ 127,536

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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