| Cover | Sep. 16, 2020 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Sep. 16, 2020 |
| Entity Registrant Name | LEVEL ONE BANCORP, INC. |
| Entity Incorporation, State or Country Code | MI |
| Entity File Number | 001-38458 |
| Entity Tax Identification Number | 71-1015624 |
| Entity Address, Address Line One | 32991 Hamilton Court |
| Entity Address, City or Town | Farmington Hills |
| Entity Address, State or Province | MI |
| Entity Address, Postal Zip Code | 48334 |
| City Area Code | (248) |
| Local Phone Number | 737-0300 |
| Written Communications | false |
| Pre-commencement Tender Offer | false |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Soliciting Material | false |
| Pre-commencement Issuer Tender Offer | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001412707 |
| Common Stock [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Common Stock, no par value |
| Trading Symbol | LEVL |
| Security Exchange Name | NASDAQ |
| Noncumulative Preferred Stock [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Depositary Shares, each representing a 1/100th interest in a share of 7.50% Non-Cumulative Perpetual Preferred Stock, Series B |
| Trading Symbol | LEVLP |
| Security Exchange Name | NASDAQ |
