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Inventories | 12 Months Ended
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Dec. 31, 2018
Inventory Disclosure [Abstract] |
Inventories | Inventories Inventories as of December 31, 2018 and December 31, 2017 consisted of the following:
| December 31, 2018 |  | December 31, 2017
| (Dollars in millions)
Materials and supplies | $ | 118.1 |  |  | $ | 101.5 |
Raw coal | 53.6 |  |  | 78.1 |
Saleable coal | 108.5 |  |  | 111.7 |
Inventories | $ | 280.2 |  |  | $ | 291.3 |
Materials and supplies inventories presented above have been shown net of reserves of $0.2 million and $0.6 million as of December 31, 2018 and 2017, respectively.

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- Definition The entire disclosure for inventory. Includes, but is not limited to, the basis of stating inventory, the method of determining inventory cost, the classes of inventory, and the nature of the cost elements included in inventory. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -URI http://asc.fasb.org/topic&trid=2126998 + Details
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