Loans, Allowance for Credit Losses - Loans, and Credit Quality - Narrative (Details) - USD ($)	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Accrued interest on loans	$ 19,000,000	$ 15,000,000
Material loans criteria for ACL-Loans adequacy calculation	250,000
Reserve for unfunded commitments	$ 3,000,000	3,000,000
Troubled debt restructurings		18,000,000
Pre-modification balance		$ 24,000,000

Material Loans Criteria For ACL-Loans Adequacy Calculation

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- Definition

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.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of accrued interest on financing receivable.

+ References

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- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

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- Definition

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

+ References

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- Definition

Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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