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Percentage of allowance for credit losses to aggregate loans.

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Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

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Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, of financing receivable on nonaccrual status. Excludes net investment in lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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Carrying amount as of the balance sheet date of all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings or defeasance; includes real and personal property; equity interests in corporations, partnerships, and joint ventures; and beneficial interests in trusts.

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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Recorded investment of consumer mortgage loan receivables secured by residential real estate properties for which formal foreclosure proceedings are in process.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The aggregate amount of the participation liability at the end of the accounting period.

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Amount of expense related to estimated loss from loan and lease transactions.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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Loans and Leases and Allowance for Credit Losses - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($) property	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($) segment property	Sep. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jan. 01, 2023 USD ($)	Dec. 31, 2022 USD ($)	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Financing Receivable, Modifications [Line Items]
Loan portfolio segments \| segment			6
Loan participation agreements	$ 0		$ 0				$ 24,585,000
Provision for loan losses		$ 974,000		$ 3,230,000
Provision for credit losses, post ASU 2019-04	795,000		1,458,000
Allowance for credit losses, post ASU 2019-04	$ 33,687,000		$ 33,687,000		$ 32,747,000
Allowance for loan losses		22,769,000		22,769,000		$ 31,989,000	$ 23,334,000	$ 21,938,000	$ 19,352,000
Percentage of allowance for credit losses to aggregate loans	1.00%		1.00%				0.72%
Nonaccrual restructured loans	$ 0		$ 0				$ 2,808,000
Nonaccrual restructuring loans, post ASU 2019-04	3,934,000		3,934,000
Troubled debt restructuring		0		0
Other real estate owned	1,370,000		1,370,000				1,436,000
Provision (recovery) charged to expense	$ 1,300,000	974,000	$ 2,300,000	3,230,000
Residential Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Number of properties in other real estate owned \| property	2		2
Other real estate owned	$ 304,000		$ 304,000
Consumer Real Estate [Member]
Financing Receivable, Modifications [Line Items]
Allowance for credit losses, post ASU 2019-04	7,156,000		7,156,000		6,748,000
Allowance for loan losses		4,008,000		4,008,000		6,146,000	4,028,000	3,835,000	3,454,000
Nonaccrual restructured loans							1,665,000
Nonaccrual restructuring loans, post ASU 2019-04	2,064,000		2,064,000
Mortgage loans in process of foreclosure	0		0
Provision (recovery) charged to expense		166,000		26,000
Consumer and Other [Member]
Financing Receivable, Modifications [Line Items]
Allowance for credit losses, post ASU 2019-04	$ 123,000		$ 123,000		$ 149,000
Allowance for loan losses		137,000		137,000		$ 149,000	136,000	$ 133,000	$ 124,000
Nonaccrual restructured loans							15,000
Provision (recovery) charged to expense		$ 151,000		$ 364,000
Trouble Debt Restructuring [Member]
Financing Receivable, Modifications [Line Items]
Troubled debt restructuring							$ 101,000