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Other Long-Term Liabilities | 3 Months Ended
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Mar. 31, 2020
Other Liabilities Disclosure [Abstract] |
Other Long-Term Liabilities | Other Long-Term Liabilities Other long-term liabilities are summarized as follows (in thousands):
| March 31, 2020 |  | December 31, 2019
Black lung obligations | $ | 29,871 |  |  | $ | 30,233 |
Other | 1,679 |  |  | 1,197 |
Total other long-term liabilities | $ | 31,550 |  |  | $ | 31,430 |

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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=6877327&loc=d3e13212-122682 + Details
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