Other Long-Term Assets (Schedule of Other Assets) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Long-term assets:
Advance coal royalties	$ 6,105	$ 10,186
Marketable equity securities available for sale at fair value (restricted)*	2,296	1,909
Other	1,923	2,122
Total other assets	$ 10,324	$ 14,217

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Breakdown from "Other Assets" reported on balance sheet.

+ References

No definition available.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of noncurrent assets classified as other.

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Carrying amount as of the balance sheet date of capitalized amounts paid for mineral royalties which will be charged against earnings after one year or beyond the normal operating cycle, if longer.

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