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Other Long-Term Liabilities | 6 Months Ended
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Jun. 30, 2021
Other Liabilities Disclosure [Abstract] |
Other Long-Term Liabilities | Other Long-Term Liabilities Other long-term liabilities are summarized as follows (in thousands):
| June 30, 2021 |  | December 31, 2020
Black lung obligations | $ | 34,147 |  |  | $ | 34,567 |
Other | 3,031 |  |  | 2,258 |
Total other long-term liabilities | $ | 37,178 |  |  | $ | 36,825 |

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- Definition The entire disclosure for other liabilities. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20,24) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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