Loans and Allowance for Credit Losses - Acquired Loan Portfolio and Acquisition Fair Value Adjustments (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2023	Dec. 31, 2022
County Bank Corp ("County") [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	$ 3,005	$ 1,464
Accretion	(807)	(651)
Transfer from non-accretable to accretable yield	0	2,192
Balance	2,198	3,005
County Bank Corp ("County") [Member] \| Purchases With Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	1,927	288
Accretion	(402)	(553)
Transfer from non-accretable to accretable yield	0	2,192
Balance	1,525	1,927
County Bank Corp ("County") [Member] \| Purchases Without Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	1,078	1,176
Accretion	(405)	(98)
Transfer from non-accretable to accretable yield	0	0
Balance	673	1,078
Community Shores Bank Corp ("Community Shores") [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	615	719
Accretion	(470)	(1,190)
Transfer from non-accretable to accretable yield	622	1,086
Balance	767	615
Community Shores Bank Corp ("Community Shores") [Member] \| Purchases With Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	615	522
Accretion	(470)	(993)
Transfer from non-accretable to accretable yield	622	1,086
Balance	767	615
Community Shores Bank Corp ("Community Shores") [Member] \| Purchases Without Credit Deterioration [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Balance	0	197
Accretion	0	(197)
Transfer from non-accretable to accretable yield	0	0
Balance	$ 0	$ 0

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.

No definition available.

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- Definition

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 15
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481906/310-30-15-2

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481696/310-30-50-2

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- Definition

Amount of accretion recognized for the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities, with evidence of deterioration of credit quality.

+ References

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- Definition

Amount of increase of reclassification from nonaccretable difference to the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

+ References

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