| Document And Entity Information | Apr. 27, 2022 |
| Document Information [Line Items] | |
| Entity, Registrant Name | PRIME MERIDIAN HOLDING COMPANY |
| Document, Type | 8-K |
| Document, Period End Date | Apr. 27, 2022 |
| Entity, Incorporation, State or Country Code | FL |
| Entity, File Number | 333-191801 |
| Entity, Tax Identification Number | 27-2980805 |
| Entity, Address, Address Line One | 1471 Timberlane Road |
| Entity, Address, City or Town | Tallahassee |
| Entity, Address, State or Province | FL |
| Entity, Address, Postal Zip Code | 32312 |
| City Area Code | 850 |
| Local Phone Number | 907-2300 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity, Emerging Growth Company | false |
| Amendment Flag | false |
| Entity, Central Index Key | 0001586454 |
