Nature of Business	6 Months Ended
Nature of Business	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Business	Nature of Business Riley Exploration Permian, Inc. ("Riley Permian", "REPX", "the Company", "Registrant", "we", "our", or "us") is a growth-oriented, independent oil and natural gas company focused on growing our conventional reserves, production and cash flow per share through the acquisition, exploration, development and production of oil, natural gas and natural gas liquids ("NGLs") in the Permian Basin. Our activities are primarily focused on the San Andres Formation, a shelf margin deposit on the Northwest Shelf. The Company was formed to focus on opportunities (i) with favorable reservoir and geological characteristics primarily for oil development, (ii) that offer large contiguous acreage positions with significant untapped potential in terms of ultimate recoverable reserves and (iii) with a high degree of operational control. Our acreage is primarily located on large, contiguous blocks in Yoakum County, Texas with additional acreage located in Lea and Roosevelt Counties, New Mexico. On February 26, 2021 (the “Closing Date”), Riley Exploration Permian, Inc., a Delaware corporation (f/k/a Tengasco, Inc. (“Tengasco”)), consummated the previously announced merger pursuant to that certain Agreement and Plan of Merger (“Merger Agreement”), dated as of October 21, 2020, by and among Tengasco, Antman Sub, LLC, a newly formed Delaware limited liability company and wholly owned subsidiary of Tengasco (“Merger Sub”), and Riley Exploration – Permian, LLC (“REP LLC”), as amended by Amendment No. 1 to Agreement and Plan of Merger, dated as of January 20, 2021, by and among Tengasco, Merger Sub and REP LLC. Pursuant to the terms of the Merger Agreement, Merger Sub merged with and into REP LLC, with REP LLC surviving as the surviving company and as a wholly-owned subsidiary of Tengasco (collectively, with the other transactions described in the Merger Agreement, the “Merger”). On the Closing Date, the Registrant changed its name from Tengasco, Inc. to Riley Exploration Permian, Inc. Our organizational structure includes wholly-owned consolidated subsidiaries through which our operations are conducted. Current Commodity Environment During 2020, a novel strain of coronavirus, SARS-CoV-2, causing a disease referred to as COVID-19, spread quickly across the globe. Federal, state and local governments mobilized to implement containment mechanisms and minimize impacts to their populations and economies. Various containment measures, which included the quarantining of cities, regions and countries, have resulted in a severe drop in general economic activity and a resulting decrease in energy demand. Currently, oil and natural gas operations are considered essential in the State of Texas and New Mexico, and the Company has not had any significant disruptions in operations. This outbreak and the related responses of governmental authorities and others to limit the spread of the virus significantly reduced global economic activity, resulting in a significant decline in the demand for oil and other commodities. These factors caused a swift and material deterioration in commodity prices for a majority of 2020, which significantly impacted our revenues for the three and six months ended March 31, 2020. However, near the end of 2020 and the beginning of 2021, oil prices steadily increased but are expected to continue to be volatile as these events evolve. The Company cannot estimate the full length or gravity of the future impacts at this time and if there is another significant decline in oil price, it could have a material adverse effect on the Company’s results of operations, financial position, liquidity and the value of oil and natural gas reserves. CARES Act and Consolidated Appropriations Act On March 27, 2020, President Trump signed into law the Coronavirus Aid, Relief and Economic Security Act ("CARES Act"), and on December 27, 2020, President Trump signed into law the Consolidated Appropriations Act. These Acts are meant to provide fast and direct economic assistance for American workers, families, and small businesses, and preserve jobs for American industries. The Company evaluated the outlook of its future operations, current financial position and liquidity and determined not to take the relief provided by the CARES Act and the Consolidated Appropriations Act.