| Document and Entity Information | Nov. 30, 2020 |
| Document And Entity Information [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 30, 2020 |
| Entity Registrant Name | Kadmon Holdings, Inc. |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-37841 |
| Entity Tax Identification Number | 27-3576929 |
| Entity Address, Address Line One | 450 East 29th Street |
| Entity Address, City or Town | New York |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 10016 |
| City Area Code | 833 |
| Local Phone Number | 900-5366 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Common stock, par value $0.001 per share |
| Trading Symbol | KDMN |
| Security Exchange Name | NASDAQ |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | true |
| Amendment Flag | false |
| Entity Central Index Key | 0001557142 |
