v3.25.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2025
May 09, 2025
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Mar. 31, 2025  
Document Transition Report false  
Securities Act File Number 001-38676  
Entity Registrant Name Bank First Corp  
Entity Incorporation, State or Country Code WI  
Entity Tax Identification Number 39-1435359  
Entity Address, Address Line One 402 North 8th Street  
Entity Address, City or Town Manitowoc  
Entity Address, State or Province WI  
Entity Address, Postal Zip Code 54220  
City Area Code 920  
Local Phone Number 652-3100  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Title of 12(b) Security Common Stock, par value $0.01 per share  
Trading Symbol BFC  
Security Exchange Name NASDAQ  
Entity Common Stock, Shares Outstanding   9,917,724
Entity Central Index Key 0001746109  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Amendment Flag false