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Short-Term Borrowings and Long-Term Debt - Summary of Short-term Debt and Long-term Debt (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025	May 06, 2021	Jan. 31, 2014
Short-Term Debt [Line Items]
Total short-term borrowings	$ 350,000	$ 330,000
Debt Instrument [Line Items]
Long-term debt	500,859	620,575
FHLB Borrowings
Short-Term Debt [Line Items]
Total short-term borrowings	350,000	300,000
Federal Funds Purchased
Short-Term Debt [Line Items]
Total short-term borrowings	$ 0	30,000
5.75% Subordinated Notes, Due 2026
Debt Instrument [Line Items]
Interest rate	5.25%			5.25%
Trust preferred securities issued	$ 0	134,509
4.00% Subordinated Notes, Due 2031
Debt Instrument [Line Items]
Interest rate	4.00%		4.00%
Trust preferred securities issued	$ 0	372,660
5.301% Senior Notes, Due February 2032
Debt Instrument [Line Items]
Interest rate			5.301%
Senior Notes	387,453	0
Floating Rate Subordinated Debentures, Due 2032 to 2036
Debt Instrument [Line Items]
Trust preferred securities issued	$ 113,406	$ 113,406