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Inventories (Details) - USD ($) $ in Thousands | Jun. 30, 2022 | Dec. 31, 2021
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Inventory Disclosure [Abstract] |  |
Coal | $ 16,855 | $ 19,352
Mining supplies | 40,101 | 34,733
Total inventories | $ 56,956 | $ 54,085

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- Definition Carrying amount as of the balance sheet date of coal, which is a combustible rock or minerals which are extracted from the ground and used as fuel. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(a)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount before valuation and LIFO reserves of other supplies used within the manufacturing or production process expected to be consumed within one year or operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(6)(a)(5)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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