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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

X

- 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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