Name:	arlp_SegmentAdjustedEBITDA
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Balance Type:	credit
Period Type:	duration

Represents the segment adjusted EBITDA expense, including operating expenses, coal purchases and other income. Excludes transportation expenses.

No definition available.

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Namespace Prefix:	arlp_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: 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(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 22
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8736-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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Period Type:	instant

The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3213-108585

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
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-Section 50
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-Subparagraph (a)
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Period Type:	duration

- References

No definition available.

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Name:	us-gaap_StatementBusinessSegmentsAxis=arlp_AppalachiaSegmentMember
Namespace Prefix:
Data Type:	na
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Data Type:	na
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Name:	us-gaap_StatementBusinessSegmentsAxis=us-gaap_CorporateAndOtherMember
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Data Type:	na
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Name:	srt_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
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Data Type:	na
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