Investment Securities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Schedule of Investments [Line Items]
AFS accrued interest	$ 1,000		$ 1,000
Held-to-maturity securities	401,561		401,561		$ 399,494
HTM accrued interest	2,400		2,400
Available-for-sale securities pledged as collateral	392,600		392,600		338,800
Net gains	0	$ 0	0	$ 0
FHLB
Schedule of Investments [Line Items]
Letter of credit outstanding, amount	$ 226,000		$ 226,000		$ 189,000