Inventories And Deferred Preservation Costs (Narrative) (Details) - USD ($) $ in Millions |
Sep. 30, 2020 |
Dec. 31, 2019 |
---|---|---|
Inventory [Line Items] | ||
Consignment inventory | $ 12.8 | $ 12.0 |
Domestic [Member] | ||
Inventory [Line Items] | ||
Consignment inventory percentage | 47.00% | 51.00% |
Foreign [Member] | ||
Inventory [Line Items] | ||
Consignment inventory percentage | 53.00% | 49.00% |