Basis of Presentation (Policies)	3 Months Ended
Mar. 31, 2024
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	The Reserve Petroleum Company, a Delaware corporation, is an independent oil and gas company engaged in oil and natural gas exploration, development and minerals management with areas of concentration in Arkansas, Kansas, Oklahoma, South Dakota, Texas and Wyoming, a single business segment. The Company is also engaged in investments and joint ventures that are not significant business segments. The Company’s consolidated subsidiaries consist of Grand Woods Development, LLC (“Grand Woods”), an Oklahoma limited liability company and wholly owned Trinity Water Services, LLC ("TWS"), an Oklahoma limited liability company. Unless otherwise specified or the context otherwise requires, all references in these notes to “the Company,” “its,” “our,” and “we” are to The Reserve Petroleum Company and its consolidated subsidiaries. The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”). The consolidated financial statements include the accounts of The Reserve Petroleum Company and its subsidiaries in which the Company holds a controlling interest, reflecting ownership of a majority of the voting interest, as of the financial statement date. Additionally, the Company consolidates Variable Interest Entities (“VIEs”) under certain criteria discussed further below. All intercompany accounts and transactions have been eliminated in consolidation. In 2023, the Company changed its presentation method on the statement of cash flows from the direct method to the indirect method. The indirect method is predominantly used in practice, provides a useful link to income statements and balance sheets, is more familiar to financial statement users and is the less costly approach to prepare. The Company has recast the Consolidated Statements of Cash Flows and related disclosures for the period ended March 31, 2023, to conform to the indirect presentation method in the current period. When necessary, reclassifications that are not material to the consolidated financial statements are made to prior period financial information to conform to the current year presentation. These reclassifications had no impact on net income or retained earnings. The accompanying consolidated financial statements and notes thereto should be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission (hereinafter the “2023 Form 10-K”). In the opinion of management, the accompanying consolidated financial statements reflect all adjustments (consisting only of normal recurring accruals), which are necessary for a fair statement of the results of the interim periods presented. The results of operations for the current interim periods are not necessarily indicative of the operating results for the full year.
Variable Interest Entities	Variable Interest Entities The Company decides at the inception of each arrangement whether an entity in which an investment is made or in which we have other variable interests is considered a VIE. Generally, an entity is a VIE if (1) the entity does not have sufficient equity at risk to finance its activities without additional subordinated financial support from other parties, (2) the entity’s investors lack any characteristics of a controlling financial interest or (3) the entity was established with non-substantive voting rights. The Company consolidates VIEs when the Company is deemed to be the primary beneficiary. The primary beneficiary of a VIE is generally the party that both: (1) has the power to make decisions that most significantly affect the economic performance of the VIE and (2) has the obligation to absorb losses or the right to receive benefits that in either case could potentially be significant to the VIE. If the Company is not deemed to be the primary beneficiary of a VIE, the Company accounts for the investment or other variable interests in a VIE in accordance with applicable GAAP.
Non-Controlling Interests	Non-Controlling Interests When the Company consolidates an entity, 100% of the assets, liabilities, revenues and expenses of the subsidiary are included in the consolidated financial statements. For those consolidated entities in which the Company’s ownership is less than 100%, the Company records a non-controlling interest as a component of equity on the consolidated balance sheets, which represents the third-party ownership in the net assets of the respective consolidated subsidiary. Additionally, the portion of the net income or loss attributable to the non-controlling interest is reported as net income (loss) attributable to non-controlling interest on the consolidated statements of income. Changes in ownership interests in an entity that do not result in deconsolidation are generally recognized within equity. See Note 5 for additional details on non-controlling interests.
New Accounting Pronouncements	New Accounting Pronouncements In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. ASU 2023-09 intends to provide investors with enhanced information about an entity’s income taxes by requiring disclosure of items such as disaggregation of the effective tax rate reconciliation as well as information regarding income taxes paid. This ASU is effective for annual reporting periods beginning after December 15, 2024, with early adoption permitted for annual financial statements that have not yet been issued. The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow. In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segments Disclosures. Under this ASU, the scope and frequency of segment disclosures is increased to provide investors with additional detail about information utilized by an entity’s “Chief Operating Decision Maker.” This ASU is effective for the Company beginning with our 2024 annual reporting and interim periods beginning in 2025. The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow. In August 2023, the FASB issued ASU 2023-05, Business Combinations-Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement. This ASU is effective for all entities for fiscal years beginning after December 15, 2024, including interim periods within those fiscal years. Early adoption is permitted for both interim and annual financial statements that have not yet been issued (or made available for issuance). If an entity adopts the amendments in an interim period, it must adopt them as of the beginning of the fiscal year that includes that interim period. This ASU applies to the formation of entities that meet the definition of a joint venture (or a corporate joint venture) as defined in the FASB Accounting Standards Codification Master Glossary. While joint ventures are defined in the Master Glossary, there has been no specific guidance in the Codification that applies to the formation accounting by a joint venture in its separate financial statements. The amendments in the ASU require that a joint venture apply a new basis of accounting upon formation. As a result, a newly formed joint venture, upon formation, would initially measure its assets and liabilities at fair value (with exceptions to fair value measurement that are consistent with the business combinations guidance). The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow.
Fair Value Measuremens	The Company uses a three-level valuation hierarchy for disclosure of fair value measurements. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows: Level 1 – Unadjusted quoted prices for identical assets or liabilities in active markets. Level 2 – Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in markets that are not active; and model-derived valuations whose inputs or significant value drivers are observable. Level 3 – These assets include investments for which there is little, if any, market activity. These inputs require significant management judgement or estimation. Recurring Fair Value Measurements Certain assets of the Company are reported at fair value in the accompanying consolidated balance sheets on a recurring basis. The Company determined the fair value of equity securities and available-for-sale debt securities using quoted market prices, public Net Asset Values ("NAV") and where applicable, securities with similar maturity dates and interest rates. Level 3 assets use NAV as fair value. Non-Recurring Fair Value Measurements The Company’s asset retirement obligation annually represents a non-recurring fair value liability, for which there were no liabilities incurred in the three months ended March 31, 2024 or 2023. See Note 8 above for more information about this liability and the inputs used for calculating fair value. There were no impairment losses recorded on oil and gas assets in the three months ended March 31, 2024. Impairment losses recorded on oil and gas assets in the three months ended March 31, 2023 were $443,456. This also relates to non-recurring fair value measurements calculated using Level 3 inputs. Certain oil and natural gas producing properties have been deemed to be impaired because the assets, evaluated on a property-by-property basis, are not expected to recover their entire carrying value through future cash flows. Impairment losses, when recorded, are included in the consolidated statements of income in the line-item Depreciation, Depletion, Amortization and Valuation Provision. Impairments are calculated by reducing the carrying value of the individual properties to an estimated fair value equal to the discounted present value of the future cash flow from these properties. Forward pricing is used for calculating future revenue and cash flow. Fair Value of Financial Instruments The Company’s other financial instruments consist primarily of cash and cash equivalents, trade receivables, and trade payables. At March 31, 2024, and December 31, 2023, the historical cost of cash and cash equivalents, trade receivables and trade payables are considered to be representative of their respective fair values due to the short-term maturities of these items.

Basis of Presentation (Policies)

3 Months Ended

Mar. 31, 2024

Organization, Consolidation and Presentation of Financial Statements [Abstract]

The Reserve Petroleum Company, a Delaware corporation, is an independent oil and gas company engaged in oil and natural gas exploration, development and minerals management with areas of concentration in Arkansas, Kansas, Oklahoma, South Dakota, Texas and Wyoming, a single business segment. The Company is also engaged in investments and joint ventures that are not significant business segments. The Company’s consolidated subsidiaries consist of Grand Woods Development, LLC (“Grand Woods”), an Oklahoma limited liability company and wholly owned Trinity Water Services, LLC ("TWS"), an Oklahoma limited liability company. Unless otherwise specified or the context otherwise requires, all references in these notes to “the Company,” “its,” “our,” and “we” are to The Reserve Petroleum Company and its consolidated subsidiaries.

The Company’s consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) and the rules and regulations of the Securities and Exchange Commission (“SEC”). The consolidated financial statements include the accounts of The Reserve Petroleum Company and its subsidiaries in which the Company holds a controlling interest, reflecting ownership of a majority of the voting interest, as of the financial statement date. Additionally, the Company consolidates Variable Interest Entities (“VIEs”) under certain criteria discussed further below. All intercompany accounts and transactions have been eliminated in consolidation.

In 2023, the Company changed its presentation method on the statement of cash flows from the direct method to the indirect method. The indirect method is predominantly used in practice, provides a useful link to income statements and balance sheets, is more familiar to financial statement users and is the less costly approach to prepare. The Company has recast the Consolidated Statements of Cash Flows and related disclosures for the period ended March 31, 2023, to conform to the indirect presentation method in the current period.

When necessary, reclassifications that are not material to the consolidated financial statements are made to prior period financial information to conform to the current year presentation. These reclassifications had no impact on net income or retained earnings.

The accompanying consolidated financial statements and notes thereto should be read in conjunction with the financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2023, as filed with the Securities and Exchange Commission (hereinafter the “2023 Form 10-K”).

In the opinion of management, the accompanying consolidated financial statements reflect all adjustments (consisting only of normal recurring accruals), which are necessary for a fair statement of the results of the interim periods presented. The results of operations for the current interim periods are not necessarily indicative of the operating results for the full year.

Variable Interest Entities

The Company decides at the inception of each arrangement whether an entity in which an investment is made or in which we have other variable interests is considered a VIE. Generally, an entity is a VIE if (1) the entity does not have sufficient equity at risk to finance its activities without additional subordinated financial support from other parties, (2) the entity’s investors lack any characteristics of a controlling financial interest or (3) the entity was established with non-substantive voting rights. The Company consolidates VIEs when the Company is deemed to be the primary beneficiary. The primary beneficiary of a VIE is generally the party that both: (1) has the power to make decisions that most significantly affect the economic performance of the VIE and (2) has the obligation to absorb losses or the right to receive benefits that in either case could potentially be significant to the VIE. If the Company is not deemed to be the primary beneficiary of a VIE, the Company accounts for the investment or other variable interests in a VIE in accordance with applicable GAAP.

Non-Controlling Interests

When the Company consolidates an entity, 100% of the assets, liabilities, revenues and expenses of the subsidiary are included in the consolidated financial statements. For those consolidated entities in which the Company’s ownership is less than 100%, the Company records a non-controlling interest as a component of equity on the consolidated balance sheets, which represents the third-party ownership in the net assets of the respective consolidated subsidiary. Additionally, the portion of the net income or loss attributable to the non-controlling interest is reported as net income (loss) attributable to non-controlling interest on the consolidated statements of income. Changes in ownership interests in an entity that do not result in deconsolidation are generally recognized within equity. See Note 5 for additional details on non-controlling interests.

New Accounting Pronouncements

In December 2023, the FASB issued ASU 2023-09, Improvements to Income Tax Disclosures. ASU 2023-09 intends to provide investors with enhanced information about an entity’s income taxes by requiring disclosure of items such as disaggregation of the effective tax rate reconciliation as well as information regarding income taxes paid. This ASU is effective for annual reporting periods beginning after December 15, 2024, with early adoption permitted for annual financial statements that have not yet been issued. The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow.

In November 2023, the FASB issued ASU 2023-07, Improvements to Reportable Segments Disclosures. Under this ASU, the scope and frequency of segment disclosures is increased to provide investors with additional detail about information utilized by an entity’s “Chief Operating Decision Maker.” This ASU is effective for the Company beginning with our 2024 annual reporting and interim periods beginning in 2025. The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow.

In August 2023, the FASB issued ASU 2023-05, Business Combinations-Joint Venture Formations (Subtopic 805-60): Recognition and Initial Measurement. This ASU is effective for all entities for fiscal years beginning after December 15, 2024, including interim periods within those fiscal years. Early adoption is permitted for both interim and annual financial statements that have not yet been issued (or made available for issuance). If an entity adopts the amendments in an interim period, it must adopt them as of the beginning of the fiscal year that includes that interim period. This ASU applies to the formation of entities that meet the definition of a joint venture (or a corporate joint venture) as defined in the FASB Accounting Standards Codification Master Glossary. While joint ventures are defined in the Master Glossary, there has been no specific guidance in the Codification that applies to the formation accounting by a joint venture in its separate financial statements. The amendments in the ASU require that a joint venture apply a new basis of accounting upon formation. As a result, a newly formed joint venture, upon formation, would initially measure its assets and liabilities at fair value (with exceptions to fair value measurement that are consistent with the business combinations guidance). The Company does not anticipate the adoption of this update to have a material impact on the Company’s financial position, results of operations or cash flow.

Fair Value Measuremens

The Company uses a three-level valuation hierarchy for disclosure of fair value measurements. The valuation hierarchy is based upon the transparency of inputs to the valuation of an asset or liability as of the measurement date. The three levels are defined as follows:

Level 1 – Unadjusted quoted prices for identical assets or liabilities in active markets.

Level 2 – Quoted prices for similar assets or liabilities in active markets; quoted prices for identical or similar assets or liabilities in markets that are not active; and model-derived valuations whose inputs or significant value drivers are observable.

Level 3 – These assets include investments for which there is little, if any, market activity. These inputs require significant management judgement or estimation.

Recurring Fair Value Measurements

Certain assets of the Company are reported at fair value in the accompanying consolidated balance sheets on a recurring basis. The Company determined the fair value of equity securities and available-for-sale debt securities using quoted market prices, public Net Asset Values ("NAV") and where applicable, securities with similar maturity dates and interest rates. Level 3 assets use NAV as fair value.

Non-Recurring Fair Value Measurements

The Company’s asset retirement obligation annually represents a non-recurring fair value liability, for which there were no liabilities incurred in the three months ended March 31, 2024 or 2023. See Note 8 above for more information about this liability and the inputs used for calculating fair value.

There were no impairment losses recorded on oil and gas assets in the three months ended March 31, 2024. Impairment losses recorded on oil and gas assets in the three months ended March 31, 2023 were $443,456. This also relates to non-recurring fair value measurements calculated using Level 3 inputs. Certain oil and natural gas producing properties have been deemed to be impaired because the assets, evaluated on a property-by-property basis, are not expected to recover their entire carrying value through future cash flows. Impairment losses, when recorded, are included in the consolidated statements of income in the line-item Depreciation, Depletion, Amortization and Valuation Provision. Impairments are calculated by reducing the carrying value of the individual properties to an estimated fair value equal to the discounted present value of the future cash flow from these properties. Forward pricing is used for calculating future revenue and cash flow.

Fair Value of Financial Instruments

The Company’s other financial instruments consist primarily of cash and cash equivalents, trade receivables, and trade payables. At March 31, 2024, and December 31, 2023, the historical cost of cash and cash equivalents, trade receivables and trade payables are considered to be representative of their respective fair values due to the short-term maturities of these items.