Assets Held For Sale (Summary Of Assets Held For Sale) (Details) - Disposal Group, Held-for-sale, Not Discontinued Operations [Member] $ in Thousands	Dec. 31, 2021 USD ($)
Long Lived Assets Held-for-sale [Line Items]
Cost	$ 5,309
Accumulated Depreciation	(4,693)
Net Book Value	616
Starkville, Mississippi [Member]
Long Lived Assets Held-for-sale [Line Items]
Cost	5,309
Accumulated Depreciation	(4,693)
Net Book Value	616
Buildings and improvements [Member] | Starkville, Mississippi [Member]
Long Lived Assets Held-for-sale [Line Items]
Cost	4,615
Accumulated Depreciation	(4,254)
Net Book Value	361
Land and Land Improvements [Member] | Starkville, Mississippi [Member]
Long Lived Assets Held-for-sale [Line Items]
Cost	694
Accumulated Depreciation	(439)
Net Book Value	$ 255