Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 05, 2019
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2019
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Trading Symbol	MR
Entity Registrant Name	Montage Resources Corporation
Entity Central Index Key	0001600470
Entity Current Reporting Status	Yes
Entity Shell Company	false
Entity File Number	001-36511
Entity Tax Identification Number	464812998
Entity Address, Address Line One	122 West John Carpenter Freeway
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Irving
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	75039
City Area Code	469
Local Phone Number	444-1647
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	true
Entity Common Stock, Shares Outstanding		35,705,270