Inventory (Narrative) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Inventory Disclosure [Abstract]
Cost of goods sold, amortization of operating materials	$ 1.4	$ 1.7
General And Administrative Costs In Inventory Amount Incurred	6.4
Fixed overhead costs	4.3
Negative operating efficiency variances cost incurred	$ 2.1