| Cover | Sep. 30, 2020 | Aug. 12, 2020 |
| Cover [Abstract] | ||
| Document Type | 8-K | |
| Amendment Flag | false | |
| Document Period End Date | Sep. 30, 2020 | |
| Entity File Number | 001-33675 | |
| Entity Registrant Name | Riot Blockchain, Inc. | |
| Entity Central Index Key | 0001167419 | |
| Entity Tax Identification Number | 84-1553387 | |
| Entity Incorporation, State or Country Code | NV | |
| Entity Address, Address Line One | 202 6th Street | |
| Entity Address, Address Line Two | Suite 401 | |
| Entity Address, City or Town | Castle Rock | |
| Entity Address, State or Province | CO | |
| Entity Address, Postal Zip Code | 80104 | |
| City Area Code | (303) | |
| Local Phone Number | 794-2000 | |
| Written Communications | false | |
| Soliciting Material | false | |
| Pre-commencement Tender Offer | false | |
| Pre-commencement Issuer Tender Offer | false | |
| Title of 12(b) Security | Common Stock | |
| Trading Symbol | RIOT | |
| Security Exchange Name | NASDAQ | |
| Entity Emerging Growth Company | false |
