Short-Term Borrowings - Components and Selected Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Short-term borrowings
Short-term borrowings	$ 500,000		$ 500,000
Federal Reserve Bank Advances [Member]
Short-term borrowings
Borrowing capacity	3,200,000		3,300,000
Federal funds purchased:
Short-term borrowings
Highest month-end balance		$ 150,000
Average outstanding balance		$ 67,056
Weighted-average interest rate paid (as a percent)		4.43%
Short-term FHLB repo advance:
Short-term borrowings
Weighted-average interest rate (as a percent)		5.00%
Highest month-end balance		$ 250,000
Average outstanding balance		$ 52,778
Weighted-average interest rate paid (as a percent)		5.02%
FHLB
Short-term borrowings
Short-term borrowings	500,000		500,000
Borrowing capacity	$ 2,900,000		$ 2,500,000
Weighted-average interest rate (as a percent)	4.71%		4.71%
Highest month-end balance	$ 500,000
Average outstanding balance	$ 500,000
Weighted-average interest rate paid (as a percent)	4.79%