| Cover | Aug. 03, 2021 |
| Document Information [Line Items] | |
| Document Type | 8-K |
| Amendment Flag | false |
| Document Period End Date | Aug. 3, 2021 |
| Entity File Number | 001-11981 |
| Entity Registrant Name | MMA Capital Holdings, Inc. |
| Entity Central Index Key | 0001003201 |
| Entity Tax Identification Number | 52-1449733 |
| Entity Incorporation, State or Country Code | DE |
| Entity Address, Address Line One | 3600 O’Donnell St. |
| Entity Address, Address Line Two | Suite 600 |
| Entity Address, City or Town | Baltimore |
| Entity Address, State or Province | MD |
| Entity Address, Postal Zip Code | 21224 |
| City Area Code | 443 |
| Local Phone Number | 263-2900 |
| Written Communications | false |
| Soliciting Material | true |
| 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 Shares, no par value |
| Trading Symbol | MMAC |
| Security Exchange Name | NASDAQ |
| Common Stock Purchase Rights [Member] | |
| Document Information [Line Items] | |
| Title of 12(b) Security | Common Stock Purchase Rights |
| Trading Symbol | MMAC |
| Security Exchange Name | NASDAQ |
