| Cover | Jun. 30, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Jun. 30, 2021 |
| Entity File Number | 001-36338 |
| Entity Registrant Name | 22nd Century Group, Inc. |
| Entity Central Index Key | 0001347858 |
| Entity Tax Identification Number | 98-0468420 |
| Entity Incorporation, State or Country Code | NV |
| Entity Address, Address Line One | 500 Seneca Street |
| Entity Address, Address Line Two | Suite 507 |
| Entity Address, City or Town | Buffalo |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 14204 |
| City Area Code | 716 |
| Local Phone Number | 270-1523 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common Stock, $0.00001 par value |
| Trading Symbol | XXII |
| Security Exchange Name | NYSEAMER |
| Entity Emerging Growth Company | false |
