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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Asset-backed Securities
Changes in Level 3
Beginning balance	$ 3,254	$ 2,270
Total gains or losses
Included in other comprehensive income	(16)	(68)
Purchases, issuances, sales, and settlements
Purchases	1,702	1,209
Settlements	(340)	(111)
Ending balance	4,600	3,300
States and political subdivisions
Changes in Level 3
Beginning balance	11,896	13,059
Total gains or losses
Included in earnings		(98)
Included in other comprehensive income	(335)	18
Purchases, issuances, sales, and settlements
Settlements	(120)	(111)
Ending balance	11,441	12,868
Mortgage Servicing rights
Changes in Level 3
Beginning balance	10,374	10,344
Total gains or losses
Included in earnings	(1,143)	(706)
Purchases, issuances, sales, and settlements
Issuances	665	490
Settlements	(347)	(402)
Ending balance	$ 9,549	$ 9,726

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