| Cover Page | Aug. 16, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 16, 2021 |
| Entity Registrant Name | Bottomline Technologies, Inc. |
| Entity Central Index Key | 0001073349 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 000-25259 |
| Entity Tax Identification Number | 02-0433294 |
| Entity Address, Address Line One | 325 Corporate Drive |
| Entity Address, Postal Zip Code | 03801-6808 |
| Entity Address, City or Town | Portsmouth, |
| Entity Address, State or Province | NH |
| City Area Code | 603 |
| Local Phone Number | 436-0700 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Title of 12(b) Security | Common Stock, $.001 par value per share |
| Trading Symbol | EPAY |
| Security Exchange Name | NASDAQ |
