v3.25.2
Document And Entity Information
Jul. 28, 2025
Document Information [Line Items]  
Entity, Registrant Name Alerus Financial Corporation
Document, Type 8-K
Document, Period End Date Jul. 28, 2025
Entity, Incorporation, State or Country Code DE
Entity, File Number 001-39036
Entity, Tax Identification Number 45-0375407
Entity, Address, Address Line One 401 Demers Avenue
Entity, Address, City or Town Grand Forks
Entity, Address, State or Province ND
Entity, Address, Postal Zip Code 58201
City Area Code 701
Local Phone Number 795-3200
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock, $1.00 par value per share
Trading Symbol ALRS
Security Exchange Name NASDAQ
Entity, Emerging Growth Company false
Amendment Flag false
Entity, Central Index Key 0000903419