Leases (Book Value Of Assets Under Operating Leases From Owned Assets) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Subject to or Available for Operating Lease [Line Items]
Gross balance	$ 556,268	$ 605,562
Accumulated depreciation	(239,115)	(252,437)
Operating property, net	317,153	353,125
Building And Improvements [Member]
Property Subject to or Available for Operating Lease [Line Items]
Gross balance	139,120	153,643
Accumulated depreciation	(21,734)	(26,107)
Operating property, net	$ 117,386	$ 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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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