Commitments and Contingencies - Financial instruments with off-Balance Sheet credit risk (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Commitments to extend credit \| Credit card lines
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	$ 6,514,524	$ 6,415,208
Commitments to extend credit \| Commercial Lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	4,260,637	4,257,505
Commitments to extend credit \| Construction Lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	1,139,056	1,197,319
Commitments to extend credit \| Other consumer unused credit commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	283,742	277,635
Commercial letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	6,838	21,248
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	97,235	111,554
Commitments to originate or fund mortgage loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	$ 20,457	$ 20,099