v3.26.1
Fair value measurement - Assets measured at fair value on nonrecurring basis (Details) - Nonrecurring - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans $ 23,568 $ 4,167
Other real estate owned 2,052 2,018
Other foreclosed assets 228 133
Total assets measured at fair value on non-recurring basis 25,848 6,318
Loans - write-down (541) (362)
Other real estate owned - write down (258) (485)
Other foreclosed assets - write down (60) (76)
Total assets measured - write down (859) (923)
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans 0 0
Other real estate owned 0 0
Other foreclosed assets 0 0
Total assets measured at fair value on non-recurring basis 0 0
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans 0 0
Other real estate owned 0 0
Other foreclosed assets 0 0
Total assets measured at fair value on non-recurring basis 0 0
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Loans 23,568 4,167
Other real estate owned 2,052 2,018
Other foreclosed assets 228 133
Total assets measured at fair value on non-recurring basis $ 25,848 $ 6,318