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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

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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 + Details
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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 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 + Details
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