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v3.19.3.a.u2

SEGMENT INFORMATION - General Information (Details) $ in Thousands | 12 Months Ended |  |  |
--- | --- | --- | --- | ---
Dec. 31, 2019 segment | Feb. 08, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jul. 19, 2017 USD ($)
Reportable segment results |  |  |  |
Number of reportable segments | 3 |  |  |
Number of coal reportable segments | 2 |  |  |
Number of mining complex | 7 |  |  |
Equity securities | $ |  |  | $ 122,094 |
Kodiak |  |  |  |
Reportable segment results |  |  |  |
Equity securities | $ |  | $ 0 |  | $ 100,000

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- Definition Amount of investment in equity security without readily determinable fair value. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 321 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714 + Details
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- Details
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