Commitments and Contingent Liabilities - Financial Instruments with Off-Balance Sheet Risk (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Financial instruments with off-balance sheet risk
Contract amount	$ 7,000,000	$ 7,000,000
Commitments to extend credit
Financial instruments with off-balance sheet risk
Contract amount	6,722,595	6,760,395
Standby letters of credit
Financial instruments with off-balance sheet risk
Contract amount	238,704	244,275
Commercial letters of credit
Financial instruments with off-balance sheet risk
Contract amount	$ 5,410	$ 7,299