v3.26.1
Cover
12 Months Ended
Sep. 30, 2025
Document Information [Line Items]  
Document Type 11-K
Entity Registrant Name Timberland Bancorp Inc
Amendment Flag false
Entity Central Index Key 0001046050
EBP 002  
Document Information [Line Items]  
Document Type 11-K
Entity Registrant Name Timberland Bancorp Inc
Amendment Flag false
Entity Central Index Key 0001046050