Loans, Allowance for Credit Losses - Loans, and Credit Quality - Schedule of Provision for Credit Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Receivables [Abstract]
Loans	$ 750	$ 450		$ 2,850	$ 1,650	$ 2,650
Unfunded commitments	0	0		0	0	0
Investment securities	0	0	$ 2,300	0	2,340	2,340
Total	$ 750	$ 450		$ 2,850	$ 3,990	$ 4,990

Credit Loss Expense (Reversal)

No definition available.

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- Definition

Debt Securities, Available-for-Sale and Held-to-Maturity, Credit Loss Expense (Reversal)

+ References

No definition available.

+ Details

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- Definition

Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. 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
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount of expense related to credit loss from transactions other than loan and lease transactions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04(11))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478524/942-220-S99-1

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- References

No definition available.

+ Details

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