| DOCUMENT AND ENTITY INFORMATION - USD ($) $ in Millions | 12 Months Ended | ||
| Dec. 31, 2019 | Mar. 10, 2020 | Jun. 28, 2019 | |
| Cover [Abstract] | |||
| Document Type | 10-K/A | ||
| Document Fiscal Period Focus | FY | ||
| Document Annual Report | true | ||
| Document Period End Date | Dec. 31, 2019 | ||
| Document Transition Report | false | ||
| Amendment Flag | true | ||
| Amendment Description | Correction of Item 6. Selected Financial Data for 2017, 2016 and 2015 | ||
| Document Fiscal Year Focus | 2019 | ||
| Current Fiscal Year End Date | --12-31 | ||
| Entity File Number | 001-33999 | ||
| Entity Registrant Name | NORTHERN OIL AND GAS, INC. | ||
| Entity Central Index Key | 0001104485 | ||
| Entity Incorporation, State or Country Code | DE | ||
| Entity Tax Identification Number | 95-3848122 | ||
| Entity Address, Address Line One | 601 Carlson Pkwy – Suite 990 | ||
| Entity Address, City or Town | Minnetonka | ||
| Entity Address, State or Province | MN | ||
| Entity Address, Postal Zip Code | 55305 | ||
| City Area Code | 952 | ||
| Local Phone Number | 476-9800 | ||
| Title of 12(b) Security | Common Stock, $0.001 par value | ||
| Trading Symbol | NOG | ||
| Security Exchange Name | NYSEAMER | ||
| Entity Well-known Seasoned Issuer | No | ||
| Entity Voluntary Filers | No | ||
| Entity Current Reporting Status | Yes | ||
| Entity Interactive Data Current | Yes | ||
| Entity Filer Category | Accelerated Filer | ||
| Entity Small Business | false | ||
| Entity Emerging Growth Company | false | ||
| Entity Shell Company | false | ||
| Entity Public Float | $ 547.5 | ||
| Entity Common Stock, Shares Outstanding | 406,021,004 | ||
| Documents Incorporated by Reference | No documents are incorporated by reference. |
