Note 20 - Subsequent Events (Details Textual) shares in Millions, $ in Millions	Oct. 23, 2020 USD ($) shares	Sep. 30, 2020
CONSOL Coal Resources L P Member
Ownership, Oustanding Common Units, Percent		60.70%
Subsequent Event [Member] \| CONSOL Coal Resources L P Member
Business Combination, Consideration Transferred, Total \| $	$ 34.4
Business Combination, Consideration Transferred, Equity Interest Acquired, Shares (in shares)	10.9
Business Combination, Consideration Transferred, Equity Interests, Shares, Exchange Ratio	0.73
Business Combination, Consideration Transferred, Equity Interests, Exchange Ratio Premium	2.10%
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	8.0
Business Acquisition, Equity Interest Issued or Issuable, Percent of Oustanding Shares	22.20%

Percent of outstanding shares of equity interests issued or issuable to acquire entity.

No definition available.

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- Definition

Number of equity interests of the acquiree acquired by the acquiring entity.

+ References

No definition available.

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The exchange ratio premium of share price of acquired entities.

+ References

No definition available.

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The exchange ratio for shares of entity acquired, paid with acquiring entity shares.

+ References

No definition available.

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The percent amount of ownership of outstanding common units.

+ References

No definition available.

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- Definition

Number of shares of equity interests issued or issuable to acquire entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
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-Section 30
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-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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