Note 2 - Acquisition for Units (Details Textual) - USD ($) $ in Thousands		12 Months Ended
Mar. 29, 2019	Dec. 31, 2020	Dec. 31, 2019
Impairment of Oil and Gas Properties		$ 0	$ 0
Limited Partners' Capital Account, Units Authorized (in shares)		20,000,000
HHC [Member]
Business Acquisition, Percentage of Net Profits Interest Acquired	96.97%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment, Total			42,900
Impairment of Oil and Gas Properties			$ 4,300
HHC [Member] \| Partnership Interest [Member]
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares (in shares)	2,400,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 43,800

Percentage of net profits interests acquired at the acquisition date in the business combination.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 30
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The amount of property, plant, and equipment recognized as of the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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-Paragraph 37
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- Definition

The expense recorded to reduce the value of oil and gas assets consisting of proved properties and unproved properties as the estimate of future successful production from these properties is reduced.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-SubTopic 10
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- Definition

The number of limited partner units authorized to be issued.

+ References

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-Name Accounting Standards Codification
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