| Cover | Oct. 13, 2021 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Oct. 13, 2021 |
| Entity File Number | 1-14100 |
| Entity Registrant Name | Impac Mortgage Holdings, Inc. |
| Entity Central Index Key | 0001000298 |
| Entity Tax Identification Number | 33-0675505 |
| Entity Incorporation, State or Country Code | MD |
| Entity Address, Address Line One | 19500 Jamboree Road |
| Entity Address, City or Town | Irvine |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 92612 |
| City Area Code | 949 |
| Local Phone Number | 475-3600 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Common Stock, $0.01 par value |
| Trading Symbol | IMH |
| Security Exchange Name | NYSEAMER |
| Preferred Stock [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Preferred Stock Purchase Rights |
| Trading Symbol | IMH |
| Security Exchange Name | NYSEAMER |
