Commitments and Contingencies - Financial instruments with off-Balance Sheet credit risk (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Commitments to extend credit | Credit card lines
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	$ 5,582,089	$ 6,108,939
Commitments to extend credit | Commercial Lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	3,874,209	3,626,269
Commitments to extend credit | Construction Lines of Credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	1,234,365	1,287,679
Commitments to extend credit | Other consumer unused credit commitments
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	261,470	256,610
Commercial letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	2,157	1,404
Standby letters of credit
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	123,685	80,889
Commitments to originate or fund mortgage loans
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Unused commitments to extend credit	$ 23,217	$ 32,968