Commitments and Contingent Liabilities - Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Financial instruments with off-balance sheet risk
Contract amount	$ 6,500,000	$ 6,500,000
Commitments to extend credit
Financial instruments with off-balance sheet risk
Contract amount	6,243,969	6,308,343
Standby letters of credit
Financial instruments with off-balance sheet risk
Contract amount	250,803	234,102
Commercial letters of credit
Financial instruments with off-balance sheet risk
Contract amount	$ 4,105	$ 3,629