XML 39 R14.htm IDEA: XBRL DOCUMENT
v3.20.4

INVENTORIES | 12 Months Ended
--- | ---
Dec. 31, 2020
INVENTORIES |
INVENTORIES |
6. | INVENTORIES
​ Inventories consist of the following: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | December 31, | ​
​ | ​ | 2020 |  | 2019 |
​ | ​ | (in thousands) | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Coal | ​ | $ | 19,756 | ​ | $ | 63,645 | ​
Supplies (net of reserve for obsolescence of $5,547 and $5,555, respectively) | ​ |  | 36,651 | ​ |  | 37,660 | ​
Total inventories, net | ​ | $ | 56,407 | ​ | $ | 101,305 | ​
​ For the year ended December 31, 2020, we recorded lower of cost or net realizable value adjustments of $3.2 million to our coal inventories as a result of lower coal sale prices and higher cost per ton due to the impact of lower production on our fixed costs per ton in addition to the impact of challenging market conditions on our production levels. The lower of cost or net realizable value adjustments reflect the impacts of the challenging market conditions and were primarily attributable to the Mettiki and Hamilton mining complexes. ​ See Note 2 – Summary of Significant Accounting Policies for more information on our accounting policy for inventories.

X
- References No definition available. + Details
Name: | us-gaap_InventoryDisclosureAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 330 -URI http://asc.fasb.org/topic&trid=2126998 + Details
Name: | us-gaap_InventoryDisclosureTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration