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Note 3 - Loans and Allowance for Loan Losses - Retail Credit Exposure (Details) - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
--- | --- | ---
Loans | $ 3,364,370,000 | $ 3,193,470,000
Retail Portfolio Segment [Member] |  |
Loans | 397,155,000 | 399,508,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] |  |
Loans | 59,311,000 | 61,620,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] | Performing Financial Instruments [Member] |  |
Loans | 59,136,000 | 61,378,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member] | Nonperforming Financial Instruments [Member] |  |
Loans | 175,000 | 242,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] |  |
Loans | 337,844,000 | 337,888,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Performing Financial Instruments [Member] |  |
Loans | 335,678,000 | 335,559,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member] | Nonperforming Financial Instruments [Member] |  |
Loans | $ 2,166,000 | $ 2,329,000

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- Definition Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524 + Details
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