| Document and Entity Information | May 07, 2024 |
| Cover [Abstract] | |
| Entity Address, Country | NL |
| Entity Tax Identification Number | 00-0000000 |
| Amendment Flag | true |
| Entity Central Index Key | 0001651311 |
| Document Type | 8-K/A |
| Document Period End Date | May 07, 2024 |
| Entity Registrant Name | MERUS N.V. |
| Entity Incorporation State Country Code | P7 |
| Entity File Number | 001-37773 |
| Entity Address, Address Line One | Uppsalalaan 17 |
| Entity Address, City or Town | 3584 CT Utrecht |
| Entity Address, Postal Zip Code | 3584 CT |
| City Area Code | 31 85 |
| Local Phone Number | 016 2500 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Shares, €0.09 nominal value per share |
| Trading Symbol | MRUS |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Amendment Description | This Amendment No. 1 on Form 8-K/A (“Amendment No. 1”) amends the Current Report on Form 8-K of Merus N.V. (the “Company”) filed with the Securities and Exchange Commission on May 8, 2024 (the “Original Report”) to amend and restate Item 5.07 summarizing the voting results at the Company’s annual general meeting of shareholders held on May 7, 2024 (the “Annual Meeting”). This amendment is for the purpose of correcting the number of abstentions reported for Proposal 2, which was reported incorrectly in the Original Report due to a typographical error. Accordingly, this Amendment No. 1 should be read in conjunction with the Original Report. |
