Cover - shares	6 Months Ended
	Mar. 31, 2021	May 06, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-15555
Entity Registrant Name	Riley Exploration Permian, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	08-0267438
Entity Address, Address Line One	29 E. Reno Avenue
Entity Address, Address Line Two	Suite 500
Entity Address, City or Town	Oklahoma City
Entity Address, State or Province	OK
Entity Address, Postal Zip Code	73104
City Area Code	405
Local Phone Number	415-8677
Title of 12(b) Security	Common stock, par value $0.001
Trading Symbol	REPX
Security Exchange Name	NYSEAMER
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		18,021,521
Entity Central Index Key	0001001614
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--09-30