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- Definition

Guarantor, Collateral Held Directly or by Third Parties, Amount

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No definition available.

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- Definition

Income Tax Receivable, Operating Loss Carryforwards

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No definition available.

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248

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- Definition

Carrying amount as of the balance sheet date of income taxes previously overpaid to tax authorities (such as U.S. Federal, state and local tax authorities) representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes. Also called income tax refund receivable.

+ 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(8))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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-Name Accounting Standards Codification
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of commitment classified as other to be paid in remainder of current fiscal year.

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fifth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in fourth fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

No definition available.

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- Definition

Amount of purchase arrangement to be paid in second fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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No definition available.

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- Definition

Amount of purchase arrangement to be paid in third fiscal year following current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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- Definition

Amount of purchase arrangement to be paid in remainder of current fiscal year. Includes, but is not limited to, recorded and unrecorded purchase obligations, long-term purchase commitment, and short-term purchase commitment.

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No definition available.

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- Definition

Amount of expense related to royalty payments under a contractual arrangement such as payment for mineral and drilling rights and use of technology or intellectual property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.3)
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

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Commitments and Contingencies (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Feb. 21, 2020	Feb. 20, 2020
Long-term Purchase Commitment [Line Items]
Coal royalty expense	$ 18,940	$ 23,946
Income tax receivable	67,862
Income tax receivable related to NOL carryback claim	64,160
Black Lung
Long-term Purchase Commitment [Line Items]
Collateral for self insurance black lunch obligations			$ 65,700	$ 2,600
Term Loan Credit Facility - due November 2025 \| Line of Credit
Long-term Purchase Commitment [Line Items]
Letters of credit outstanding	119,676
ANR, Inc. and Citibank, N.A. Credit Agreement \| Line of Credit
Long-term Purchase Commitment [Line Items]
Letters of credit outstanding	14,242
Credit and Security Agreement \| Line of Credit
Long-term Purchase Commitment [Line Items]
Letters of credit outstanding	613
Coal Purchase Agreements
Long-term Purchase Commitment [Line Items]
Minimum quantities to be purchased, remainder of fiscal year	30,491
Equipment Purchase Agreements
Long-term Purchase Commitment [Line Items]
Minimum quantities to be purchased, remainder of fiscal year	28,579
Minimum quantities to be purchased, second year	16,649
Minimum quantities to be purchased, third year	279
Minimum quantities to be purchased, fourth year	0
Minimum quantities to be purchased, fifth year	1,335
Shipping
Long-term Purchase Commitment [Line Items]
Minimum royalty obligations, 2021	42,885
Reclamation-related obligations
Long-term Purchase Commitment [Line Items]
Guarantees	396,397
Collateral supporting guarantees	82,803
Royalty Agreements \| Coal
Long-term Purchase Commitment [Line Items]
Minimum royalty obligations, 2020	11,026
Minimum royalty obligations, 2021	15,974
Minimum royalty obligations, 2022	14,081
Minimum royalty obligations, 2023	13,064
Minimum royalty obligations, 2024	11,110
Minimum royalty obligations, after 2024	$ 46,274