Basis of Presentation (Details) - Feralloy Processing Company		6 Months Ended
Mar. 31, 2020	Jun. 30, 2020	Mar. 30, 2020	Dec. 31, 2019
Basis of Presentation
Ownership percentage acquired	49.00%	49.00%
Ownership percentage in consolidated investments other than equity method investment	100.00%	100.00%	51.00%	51.00%

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