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Note 8 - Commitments and Off-balance Sheet Risk - Exposure to Credit Losses (Details) - USD ($) | Sep. 30, 2021 | Dec. 31, 2020
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Contractual amounts of financial instruments with off-balance sheet risk | $ 1,573,219,000 | $ 1,430,195,000
Standby Letters of Credit [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 29,375,000 | 20,543,000
Unused lines of Credit [Member] | Commercial Portfolio Segment [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 1,080,801,000 | 1,019,496,000
Unused lines of Credit [Member] | One to Four Family Mortgages [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 60,859,000 | 59,396,000
Unused lines of Credit [Member] | Consumer Credit Card [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 88,013,000 | 72,495,000
Unused lines of Credit [Member] | Consumer Other Financing Receivable 1 [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | 61,047,000 | 30,707,000
Loan Origination Commitments [Member] |  |
Contractual amounts of financial instruments with off-balance sheet risk | $ 253,124,000 | $ 227,558,000

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- Definition The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 + Details
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