The minimum amount of royalties to be paid annually to the related party, per the terms of the agreement.

No definition available.

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- Definition

Term of lessee's lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Excludes operating, finance and capital lease obligations.

+ References

No definition available.

+ Details

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- Definition

The percentage of earned royalty on the coal sales price provided to the counterparty under the lease agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	arlp_
Data Type:	num:percentItemType
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Period Type:	instant

- Definition

Percentage of internal rate of return provided to the counterparty in the purchase price under the option to acquire the leased coal reserves.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Period following a specified date, within which the entity has the option to acquire the coal reserves under the lease agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	arlp_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of expenses incurred but not yet paid classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.15(a))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.15(5))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118582676&loc=SL6759159-111685

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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Data Type:	na
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RELATED-PARTY TRANSACTIONS - WKY CoalPlay and Cavalier Minerals (Details) - USD ($) $ in Millions	1 Months Ended		12 Months Ended
	Feb. 28, 2015	Dec. 31, 2014	Dec. 31, 2019	Sep. 30, 2019	Jan. 03, 2019
WKY CoalPlay \| February 2015 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
Initial term of lease	20 years
Percentage of earned royalty on coal sale price	4.00%
Annual minimum royalties	$ 2.1
Period for option to acquire the leased reserves	3 years
Percentage of internal rate of return on purchase price, if leased reserves acquired	7.00%
WKY CoalPlay \| December 2014 coal lease - Henderson and Union Counties, Kentucky
Related Party Transaction
Initial term of lease		20 years
Percentage of earned royalty on coal sale price		4.00%
Annual minimum royalties		$ 3.6
Period for option to acquire the leased reserves		3 years
Percentage of internal rate of return on purchase price, if leased reserves acquired		7.00%
WKY CoalPlay \| December 2014 coal lease - Webster County, Kentucky
Related Party Transaction
Initial term of lease		7 years
Percentage of earned royalty on coal sale price		4.00%
Annual minimum royalties		$ 2.6
Period for option to acquire the leased reserves		3 years
Percentage of internal rate of return on purchase price, if leased reserves acquired		7.00%
Accrued payments				$ 5.1
WKY CoalPlay \| December 2014 coal lease - Henderson County, Kentucky
Related Party Transaction
Annual minimum royalties		$ 2.5
Cavalier Minerals
Related Party Transaction
Ownership interest in VIE (as a percent)			96.00%
Cavalier Minerals \| Bluegrass Minerals
Related Party Transaction
Noncontrolling ownership interest (as a percent)			4.00%		4.00%