Investment Securities Gross Unrealized Losses - AFS (Details) $ in Thousands	Sep. 30, 2025 USD ($) securities	Dec. 31, 2024 USD ($) securities
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months, fair value	$ 0	$ 5,095
Securities available for sale, continuous unrealized loss position, less than 12 months, accumulated loss	$ 0	$ (274)
Securities available for sale, continuous unrealized loss position, less than 12 months, Number of Positions \| securities	0	8
Securities available for sale, continuous unrealized loss position, 12 months or longer, fair value	$ 520,714	$ 520,495
Securities available for sale, continuous unrealized loss position, 12 months or longer, accumulated loss	$ (103,104)	$ (128,564)
Securities, available for sale, continuous unrealized loss position, 12 Months or longer, Number of Positions \| securities	195	192
Securities available for sale, continuous unrealized loss position, fair value	$ 520,714	$ 525,590
Securities available for sale, continuous unrealized loss position, accumulated loss	(103,104)	(128,838)
State and political subdivisions [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months, fair value	0	4,485
Securities available for sale, continuous unrealized loss position, less than 12 months, accumulated loss	$ 0	$ (271)
Securities available for sale, continuous unrealized loss position, less than 12 months, Number of Positions \| securities	0	7
Securities available for sale, continuous unrealized loss position, 12 months or longer, fair value	$ 173,161	$ 169,650
Securities available for sale, continuous unrealized loss position, 12 months or longer, accumulated loss	$ (39,145)	$ (41,526)
Securities, available for sale, continuous unrealized loss position, 12 Months or longer, Number of Positions \| securities	94	90
Securities available for sale, continuous unrealized loss position, fair value	$ 173,161	$ 174,135
Securities available for sale, continuous unrealized loss position, accumulated loss	(39,145)	(41,797)
Collateralized mortgage obligations [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months, fair value	0	0
Securities available for sale, continuous unrealized loss position, less than 12 months, accumulated loss	$ 0	$ 0
Securities available for sale, continuous unrealized loss position, less than 12 months, Number of Positions \| securities	0	0
Securities available for sale, continuous unrealized loss position, 12 months or longer, fair value	$ 217,097	$ 219,264
Securities available for sale, continuous unrealized loss position, 12 months or longer, accumulated loss	$ (43,449)	$ (59,490)
Securities, available for sale, continuous unrealized loss position, 12 Months or longer, Number of Positions \| securities	68	69
Securities available for sale, continuous unrealized loss position, fair value	$ 217,097	$ 219,264
Securities available for sale, continuous unrealized loss position, accumulated loss	(43,449)	(59,490)
Mortgage-backed securities [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months, fair value	0	610
Securities available for sale, continuous unrealized loss position, less than 12 months, accumulated loss	$ 0	$ (3)
Securities available for sale, continuous unrealized loss position, less than 12 months, Number of Positions \| securities	0	1
Securities available for sale, continuous unrealized loss position, 12 months or longer, fair value	$ 117,564	$ 119,209
Securities available for sale, continuous unrealized loss position, 12 months or longer, accumulated loss	$ (19,652)	$ (26,170)
Securities, available for sale, continuous unrealized loss position, 12 Months or longer, Number of Positions \| securities	25	25
Securities available for sale, continuous unrealized loss position, fair value	$ 117,564	$ 119,819
Securities available for sale, continuous unrealized loss position, accumulated loss	(19,652)	(26,173)
Corporate notes [Member]
Debt Securities, Available-for-sale [Line Items]
Securities available for sale, continuous unrealized loss position, less than 12 months, fair value	0	0
Securities available for sale, continuous unrealized loss position, less than 12 months, accumulated loss	$ 0	$ 0
Securities available for sale, continuous unrealized loss position, less than 12 months, Number of Positions \| securities	0	0
Securities available for sale, continuous unrealized loss position, 12 months or longer, fair value	$ 12,892	$ 12,372
Securities available for sale, continuous unrealized loss position, 12 months or longer, accumulated loss	$ (858)	$ (1,378)
Securities, available for sale, continuous unrealized loss position, 12 Months or longer, Number of Positions \| securities	8	8
Securities available for sale, continuous unrealized loss position, fair value	$ 12,892	$ 12,372
Securities available for sale, continuous unrealized loss position, accumulated loss	$ (858)	$ (1,378)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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