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Note 4 - Loans Receivable - Loans Individually Evaluated for Impairment By Class (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Loan balance, with no allowance recorded | $ 2,316 | $ 2,589
Recorded investment, with no allowance recorded | 2,083 | 2,238
Partial charge-off, with no allowance recorded | 236 | 363
Average investment in impaired loans, with no allowance recorded | 2,152 | 2,376
Interest income recognized, with no related allowance recorded | 15 | 73
Recorded investment, with an allowance recorded | 2,379 | 2,534
Partial charge-off, with allowance recorded | 236 | 363
Allowance for loan losses | 28 | 28
Average investment in impaired loans, with allowance recorded | 2,448 | 2,665
Interest income recognized, with related allowance recorded | 15 | 73
Loan balance, with allowance recorded | 2,596 | 2,869
Recorded investment, with no allowance recorded | 2,083 | 2,238
Loan balance, with allowance recorded | 2,596 | 2,869
Nonresidential Real Estate Loans [Member] |  |
Loan balance, with allowance recorded | 280 | 280
Recorded investment, with an allowance recorded | 296 | 296
Partial charge-off, with allowance recorded | 0 | 0
Allowance for loan losses | 28 | 28
Average investment in impaired loans, with allowance recorded | 296 | 289
Interest income recognized, with related allowance recorded | 0 | 0
Loan balance, with allowance recorded | 280 | 280
Real Estate Portfolio [Member] | One-to-Four Family Residential Real Estate [Member] |  |
Loan balance, with no allowance recorded | 1,801 | 2,069
Recorded investment, with no allowance recorded | 1,568 | 1,718
Partial charge-off, with no allowance recorded | 236 | 363
Average investment in impaired loans, with no allowance recorded | 1,634 | 1,782
Interest income recognized, with no related allowance recorded | 8 | 42
Recorded investment, with no allowance recorded | 1,568 | 1,718
Real Estate Portfolio [Member] | Multi-family Mortgage [Member] | ILLINOIS |  |
Loan balance, with no allowance recorded | 515 | 520
Recorded investment, with no allowance recorded | 515 | 520
Partial charge-off, with no allowance recorded | 0 | 0
Average investment in impaired loans, with no allowance recorded | 518 | 594
Interest income recognized, with no related allowance recorded | 7 | 31
Recorded investment, with no allowance recorded | $ 515 | $ 520

X
- Definition Amount of partial charge offs for impaired financing receivables for which there is no related allowance for credit losses + References No definition available. + Details
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- Definition Represents partial charge-offs with related allowance of impaired financing receavbel. + References No definition available. + Details
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- Definition Amount of allowance for credit losses related to recorded investment. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524 + Details
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- Definition Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (a)(4) -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524 + Details
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- Definition Amount of interest income, recognized on cash basis, on financing receivables, for which there is no related allowance for credit losses and are recognized as impaired. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 15 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524 + Details
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