| Cover | Oct. 12, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Oct. 12, 2021 |
| Entity Registrant Name | Apollo Endosurgery, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-35706 |
| Entity Tax Identification Number | 16-1630142 |
| Entity Address, Address Line One | 1120 S. Capital of Texas Highway |
| Entity Address, Address Line Two | Building 1, Suite #300 |
| Entity Address, City or Town | Austin |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 78746 |
| City Area Code | 512 |
| Local Phone Number | 279-5100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, $0.001 par value per share |
| Trading Symbol | APEN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001251769 |
| Amendment Flag | false |
