v3.26.1
Document and Entity Information
Jul. 28, 2026
Cover [Abstract]  
Entity Registrant Name FB Bancorp, Inc. /MD/
Amendment Flag false
Entity Central Index Key 0002013639
Document Type 8-K
Document Period End Date Jul. 28, 2026
Entity Incorporation, State or Country Code MD
Entity File Number 001-42380
Entity Tax Identification Number 99-1859402
Entity Address, Address Line One 353 Carondelet Street
Entity Address, City or Town New Orleans
Entity Address, State or Province LA
Entity Address, Postal Zip Code 70130
City Area Code 504
Local Phone Number 569-8640
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Title of 12(b) Security Common Stock
Trading Symbol FBLA
Security Exchange Name NASDAQ
Entity Emerging Growth Company true
Entity Ex Transition Period false