CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($)	Sep. 30, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Securities available-for-sale, amortized cost	$ 1,326,894,000	$ 1,418,337,000
Credit loss recognized	0	0
Securities held-to-maturity, allowance for credit losses	0	0
Securities held-to-maturity	$ 582,592,000	$ 642,097,000
Common stock, par value (in dollars per share)	$ 1	$ 1
Common stock, shares authorized (in shares)	80,000,000	40,000,000
Common stock, shares issued (in shares)	32,343,411	25,275,369
Treasury stock (in shares)	1,249,607	1,249,607