| Cover | Apr. 27, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Apr. 27, 2021 |
| Entity Incorporation, State or Country Code | CA |
| Entity File Number | 001-38317 |
| Entity Tax Identification Number | 68-0270948 |
| Entity Address, Address Line One | 520 Third St, Fourth Floor |
| Entity Address, City or Town | Santa Rosa |
| Entity Address, State or Province | CA |
| Entity Address, Postal Zip Code | 95401 |
| City Area Code | 844 |
| Local Phone Number | 446-8201 |
| Title of 12(b) Security | Common stock, no par value |
| Trading Symbol | LBC |
| Security Exchange Name | NASDAQ |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity Registrant Name | Luther Burbank Corp. |
| Entity Central Index Key | 0001475348 |
| Amendment Flag | false |
