| Cover Page | Jul. 13, 2020 |
| Cover [Abstract] | |
| Amendment Flag | false |
| Entity Central Index Key | 0001603756 |
| Document Type | 8-K |
| Document Period End Date | Jul. 13, 2020 |
| Entity Registrant Name | Axonics Modulation Technologies, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-38721 |
| Entity Tax Identification Number | 45-4744083 |
| Entity Address, Address Line One | 26 Technology Drive |
| Entity Address, City or Town | Irvine |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92618 |
| City Area Code | 949 |
| Local Phone Number | 396-6322 |
| 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 | true |
| Title of 12(b) Security | Common stock, par value $0.0001 per share |
| Trading Symbol | AXNX |
| Security Exchange Name | NASDAQ |
