| Document And Entity Information | Sep. 20, 2021 |
| Document Information [Line Items] | |
| Entity, Registrant Name | AQUA METALS, INC. |
| Document, Type | 8-K |
| Document, Period End Date | Sep. 20, 2021 |
| Entity, Incorporation, State or Country Code | DE |
| Entity, File Number | 001-37515 |
| Entity, Tax Identification Number | 47-1169572 |
| Entity, Address, Address Line One | 5370 Kietzke Lane |
| Entity, Address, Address Line Two | Suite 201 |
| Entity, Address, City or Town | Reno |
| Entity, Address, State or Province | NV |
| Entity, Address, Postal Zip Code | 89511 |
| City Area Code | 775 |
| Local Phone Number | 446-5486 |
| 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 |
| Trading Symbol | AQMS |
| Security Exchange Name | NASDAQ |
| Amendment Flag | false |
| Entity, Central Index Key | 0001621832 |
