Represents the renewal term for the oil and gas property management service agreement.

No definition available.

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- Definition

Represents the period for which the management company will provide transition services upon termination of the oil and gas property management service agreement.

+ References

No definition available.

+ Details

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- Definition

Amount of fees paid to the management company for running the Company's day-to-day business functions.

+ References

No definition available.

+ Details

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Namespace Prefix:	grnt_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of transactions with related party during the financial reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 850
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-13

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-Topic 946
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- Details

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Period Type:

- Details

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Period Type:

- Details

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Related Party Transactions (Details) - Related Party - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Grey Rock Administration, LLC (the Manager)
Related party transactions
Annual service fee			$ 10.0
Oil and gas management agreement, renewal term			1 year
Oil and gas management agreement, transition services term			90 days
Investment Advisor Under Funds Control
Related party transactions
Management service fees	$ 2.5	$ 2.5	$ 7.5	$ 7.5