v3.25.4
Accumulated other comprehensive income (loss) - Net Change of AOCL Components (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Other comprehensive income (loss), net of taxes $ 91,260 $ 14,783 $ 67,254
Unrealized net gains (losses) on translation of net investment in foreign operations      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Other comprehensive income (loss), net of taxes 6,419 (713) 222
Unrealized net gains (losses) on translation of net investment in foreign operations | Defined benefit pension plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
OCI, before reclassifications, net of tax (562) 132 (259)
Unrealized net gains (losses) on translation of net investment in foreign operations | Available-for-sale securities      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
OCI, before reclassifications, net of tax (2,259) 280 (2,778)
Foreign currency translation adjustments      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax 33,254 (8,876) 19,420
Gains (losses) on net investment hedge      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax (26,835) 8,163 (19,198)
Accumulated net investment gain (loss)      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Other comprehensive income (loss), net of taxes 73,988 635 57,435
Accumulated net investment gain (loss) | Held-to-maturity securities      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax 7,895 8,148 9,145
Other comprehensive income (loss), net of taxes 7,895 8,148 9,145
Accumulated net investment gain (loss) | Available-for-sale securities      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax 0 0 14
OCI, before reclassifications, net of tax 76,247 355 60,199
Other comprehensive income (loss), net of taxes 73,988 635 57,435
Employee benefit plans adjustments      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Other comprehensive income (loss), net of taxes 2,958 6,713 452
Employee benefit plans adjustments | Defined benefit pension plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax (82) (79) (79)
OCI, before reclassifications, net of tax (1,135) 0 0
Other comprehensive income (loss), net of taxes 2,165 2,281 (3,658)
Employee benefit plans adjustments | Post-retirement healthcare plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Other comprehensive income (loss), net of taxes 793 4,432 4,110
Net actuarial gain (loss) | Defined benefit pension plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax 2,341 2,358 2,284
OCI, before reclassifications, net of tax 1,439 (288) (5,762)
Net actuarial gain (loss) | Post-retirement healthcare plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax (602) 524 524
OCI, before reclassifications, net of tax 871 6,219 4,919
Prior service credit (cost) arising during the year | Post-retirement healthcare plan      
Accumulated Other Comprehensive Income (Loss) [Line Items]      
Reclassifications, net of tax $ 524 $ (2,311) $ (1,333)