| Document and Entity Information | Feb. 13, 2024 |
| Document And Entity Information [Line Items] | |
| Entity Registrant Name | NewAmsterdam Pharma Co N.V. |
| Entity Address, Country | NL |
| Entity Tax Identification Number | 00-0000000 |
| Amendment Flag | false |
| Entity Central Index Key | 0001936258 |
| Document Type | 8-K |
| Document Period End Date | Feb. 13, 2024 |
| Entity Incorporation State Country Code | P7 |
| Entity File Number | 001-41562 |
| Entity Address, Address Line One | Gooimeer 2-35 |
| Entity Address, City or Town | Naarden |
| Entity Address, Postal Zip Code | 1411 DC |
| City Area Code | +31 |
| Local Phone Number | (0) 35 206 2971 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Fair Value Measured at Net Asset Value Per Share [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Ordinary Shares, nominal value €0.12 per share |
| Trading Symbol | NAMS |
| Security Exchange Name | NASDAQ |
| Ordinary Shares Nominal Value 0.12 Per Share [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Warrants to purchase Ordinary Shares |
| Trading Symbol | NAMSW |
| Security Exchange Name | NASDAQ |
