Note 12 - Other Accrued Liabilities - Other Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Subsidence Liability	$ 92,090	$ 89,554
Accrued Payroll and Benefits	21,232	21,179
Commodity Derivatives	16,867	0
Accrued Interest	7,587	6,236
Accrued Other Taxes	4,564	7,126
Litigation	3,335	3,625
Accrued Equipment Obligations	2,302	6,698
Other	21,485	20,220
Asset Retirement Obligations	26,020	20,587
Postretirement Benefits Other than Pensions	25,662	26,073
Pneumoconiosis Benefits	12,063	12,203
Workers' Compensation	9,552	9,653
Total Other Accrued Liabilities	$ 242,759	$ 223,154

Represents current accrued derivative liability.

No definition available.

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- Definition

Carrying value as of the balance sheet date of obligations incurred through that date and payable for equipment obligations. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

No definition available.

+ Details

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Balance Type:	credit
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- Definition

Represents information related to current accrued payroll and employee benefits.

+ References

No definition available.

+ Details

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- Definition

Represents current accrued subsidence liability.

+ References

No definition available.

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- Definition

Represents current medical and disability for employee related liabilities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Represents current liability for other postretirement defined benefit plan.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable for real and property taxes. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 30
-Section 45
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=124098289&loc=d3e6935-107765

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- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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- Definition

Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Carrying value as of the balance sheet date of [accrued] interest payable on all forms of debt, including trade payables, that has been incurred and is unpaid. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Carrying amount of reserve for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs, which is expected to be paid within one year of the date of the statement of financial position.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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-Publisher FASB
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- Definition

Carrying value as of the balance sheet date of obligations and payables pertaining to claims incurred of a workers compensation nature. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

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