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Loans and Allowance for Credit Losses - Acquired Portfolio and The Acquisition Fair Value Adjustments (Details) - USD ($) $ in Thousands | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Jan. 01, 2020 | Oct. 01, 2019
County Bank Corp ("County") [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  |  | $ 395,123
Nonaccretable difference |  |  |  |  |  | (2,928)
Expected cash flows |  |  |  |  |  | 392,195
Accretable yield |  |  |  |  |  | (2,079)
Carrying balance at acquisition date |  |  |  |  |  | 390,116
Balance | $ 1,464 | $ 1,659 | $ 2,004 | $ 0 |  |
Merger |  |  |  | 2,079 |  |
Accretion | (651) | (595) | (345) | (75) |  |
Transfer from non-accretable to accretable yield | 2,192 | 400 |  |  |  |
Balance | 3,005 | 1,464 | 1,659 | 2,004 |  |
County Bank Corp ("County") [Member] | Acquired Impaired [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  |  | 7,729
Nonaccretable difference |  |  |  |  |  | (2,928)
Expected cash flows |  |  |  |  |  | 4,801
Accretable yield |  |  |  |  |  | (185)
Carrying balance at acquisition date |  |  |  |  |  | 4,616
Balance | 288 | 135 | 185 | 0 |  |
Merger |  |  |  | 185 |  |
Accretion | (553) | (247) | (50) | 0 |  |
Transfer from non-accretable to accretable yield | 2,192 | 400 |  |  |  |
Balance | 1,927 | 288 | 135 | 185 |  |
County Bank Corp ("County") [Member] | Acquired Non-Impaired [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  |  | 387,394
Nonaccretable difference |  |  |  |  |  | 0
Expected cash flows |  |  |  |  |  | 387,394
Accretable yield |  |  |  |  |  | (1,894)
Carrying balance at acquisition date |  |  |  |  |  | $ 385,500
Balance | 1,176 | 1,524 | 1,819 | 0 |  |
Merger |  |  |  | 1,894 |  |
Accretion | (98) | (348) | (295) | (75) |  |
Transfer from non-accretable to accretable yield | 0 | 0 |  |  |  |
Balance | 1,078 | 1,176 | 1,524 | 1,819 |  |
Community Shores Bank Corp ("Community Shores") [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  | $ 178,986 |
Nonaccretable difference |  |  |  |  | (2,719) |
Expected cash flows |  |  |  |  | 176,267 |
Accretable yield |  |  |  |  | (1,465) |
Carrying balance at acquisition date |  |  |  |  | 174,802 |
Balance | 719 | 1,298 | 0 |  |  |
Merger |  |  | 1,465 |  |  |
Accretion | (1,190) | (579) | (167) |  |  |
Transfer from non-accretable to accretable yield | 1,086 |  |  |  |  |
Balance | 615 | 719 | 1,298 | 0 |  |
Community Shores Bank Corp ("Community Shores") [Member] | Acquired Impaired [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  | 20,491 |
Nonaccretable difference |  |  |  |  | (2,719) |
Expected cash flows |  |  |  |  | 17,772 |
Accretable yield |  |  |  |  | (869) |
Carrying balance at acquisition date |  |  |  |  | 16,903 |
Balance | 522 | 843 | 0 |  |  |
Merger |  |  | 869 |  |  |
Accretion | (993) | (321) | (26) |  |  |
Transfer from non-accretable to accretable yield | 1,086 |  |  |  |  |
Balance | 615 | 522 | 843 | 0 |  |
Community Shores Bank Corp ("Community Shores") [Member] | Acquired Non-Impaired [Member] |  |  |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |  |  |
Loans acquired - contractual payments |  |  |  |  | 158,495 |
Nonaccretable difference |  |  |  |  | 0 |
Expected cash flows |  |  |  |  | 158,495 |
Accretable yield |  |  |  |  | (596) |
Carrying balance at acquisition date |  |  |  |  | $ 157,899 |
Balance | 197 | 455 | 0 |  |  |
Merger |  |  | 596 |  |  |
Accretion | (197) | (258) | (141) |  |  |
Transfer from non-accretable to accretable yield | 0 |  |  |  |  |
Balance | $ 0 | $ 197 | $ 455 | $ 0 |  |

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- Definition The aggregate excess of a loan's cash flows expected to be collected over the investor's initial investment in the loan. This relates to loans with deteriorating of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + References No definition available. + Details
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- Definition The recorded balance, net of any applicable reductions (for example, unamortized accretable yield and allowance for loan losses). This relates to loans not accounted for debt securities with evidence of deterioration of credit quality since origination that were acquired by completion of a transfer for which it is probable, at acquisition, that the investor will be unable to collect all contractually required payments receivable. + 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)(1) -Publisher FASB -URI https://asc.fasb.org//1943274/2147481696/310-30-50-2 + Details
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