| Document and Entity Information | Apr. 12, 2021 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001227636 |
| Document Type | 8-K |
| Document Period End Date | Apr. 12, 2021 |
| Entity Registrant Name | NEURONETICS, INC. |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-38546 |
| Entity Tax Identification Number | 33-1051425 |
| Entity Address, Address Line One | 3222 Phoenixville Pike |
| Entity Address, City or Town | Malvern |
| Entity Address, State or Province | PA |
| Entity Address, Postal Zip Code | 19355 |
| City Area Code | (610) |
| Local Phone Number | 640-4202 |
| Security 12b Title | Common Stock ($0.01 par value) |
| Trading Symbol | STIM |
| Security Exchange Name | NASDAQ |
| 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 |
