Borrowings - Securities Sold Under Agreements to Repurchase and Federal Funds Purchased (Details)	9 Months Ended	12 Months Ended
	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Assets Sold under Agreements to Repurchase [Line Items]
Securities sold under agreements to repurchase	$ 12,486,000	$ 13,499,000
Securities sold under agreements to repurchase, average rate paid	0.17%	0.20%
Percentage of fair value of securities pledged of the outstanding balance of repurchase agreement	1
Weighted average interest rate at period-end	4.23%	0.20%
Collateral Pledged
Assets Sold under Agreements to Repurchase [Line Items]
Letter of credit pledged	$ 95,000,000	$ 0
Weighted average interest rate at period-end	4.77%
Federal Funds Purchased
Assets Sold under Agreements to Repurchase [Line Items]
Line of credit	$ 405,000,000	$ 370,000,000