v3.26.1
Cover
12 Months Ended
Dec. 31, 2025
Document Information [Line Items]  
Document Type 11-K
Entity Registrant Name Flagstar Bank, National Association
Amendment Flag false
Entity Central Index Key 0000910073
EBP 004  
Document Information [Line Items]  
Document Type 11-K
Entity Registrant Name Flagstar Bank, National Association
Amendment Flag false
Entity Central Index Key 0000910073