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Note 3 - Loans and Allowance for Loan Losses - Acquired Portfolio and the Acquisition Fair Value Adjustments (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019 | Jul. 01, 2020 | Oct. 01, 2019
Community Shores Bank Corp ("Community Shores") [Member] |  |  |  |  |
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 | $ 1,298 | $ 0 |  |  |
Merger |  | 1,465 |  |  |
Accretion | (526) | (167) |  |  |
Balance | 772 | 1,298 | $ 0 |  |
Merger |  | 1,465 |  |  |
Community Shores Bank Corp ("Community Shores") [Member] | Acquired Impaired [Member] |  |  |  |  |
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 | 843 | 0 |  |  |
Merger |  | 869 |  |  |
Accretion | (328) | (26) |  |  |
Balance | 515 | 843 | 0 |  |
Merger |  | 869 |  |  |
Community Shores Bank Corp ("Community Shores") [Member] | Acquired Non-Impaired [Member] |  |  |  |  |
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 | 455 | 0 |  |  |
Merger |  | 596 |  |  |
Accretion | (198) | (141) |  |  |
Balance | 257 | 455 | 0 |  |
Merger |  | 596 |  |  |
County Bank Corp ("County") [Member] |  |  |  |  |
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 | 1,659 | 2,004 | 0 |  |
Merger |  |  | 2,079 |  |
Accretion | (81) | (345) | (75) |  |
Balance | 1,578 | 1,659 | 2,004 |  |
Merger |  |  | 2,079 |  |
County Bank Corp ("County") [Member] | Acquired Impaired [Member] |  |  |  |  |
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 | 135 | 185 | 0 |  |
Merger |  |  | 185 |  |
Accretion | (5) | (50) | 0 |  |
Balance | 130 | 135 | 185 |  |
Merger |  |  | 185 |  |
County Bank Corp ("County") [Member] | Acquired Non-Impaired [Member] |  |  |  |  |
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 | 1,524 | 1,819 | 0 |  |
Merger |  |  | 1,894 |  |
Accretion | (76) | (295) | (75) |  |
Balance | $ 1,448 | $ 1,524 | 1,819 |  |
Merger |  |  | $ 1,894 |  |

X
- 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 amount of the loan's contractually required payments receivable in excess of the amount of its cash flows expected to be collected. 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 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 -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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- Definition Amount of additions 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(2) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 + Details
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- Definition Amount of contractually required payments receivable at acquisition of 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 -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538 + 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 -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 30 -Section 15 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121585399&loc=d3e13503-111538 + Details
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