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Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans, Average Investment and Interest Income (Details) - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2020

Dec. 31, 2019

Dec. 31, 2018

Average recorded investment in impaired loans(1)

$ 5,093

^[1]

$ 5,359

^[1]

$ 9,788

^[2]

Income recognized on impaired loans, after designation as impaired

54

171

250

Investor Owned Residential Real Estate [Member] | Consumer Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

196

439

808

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

13

17

23

Equity Lines [Member] | Consumer Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

98

Income recognized on impaired loans, after designation as impaired

6

Closed End First Liens [Member] | Consumer Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

225

^[1]

1,202

Income recognized on impaired loans, after designation as impaired

11

^[1]

41

Closed End Junior Liens [Member] | Consumer Real Estate Portfolio Segment [Member] | Financing Receivables 30 to 89 Days Past Due [Member]

Average recorded investment in impaired loans(1)

^[3]

159

Closed End Junior Liens [Member] | Consumer Real Estate Portfolio Segment [Member] | Financial Asset, Equal to or Greater than 90 Days Past Due [Member]

Income recognized on impaired loans, after designation as impaired

^[3]

9

Commercial Real Estate, Owner Occupied [Member] | Commercial Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

3,217

913

3,038

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

19

41

75

Commercial Real Estate Other [Member] | Commercial Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

790

2,435

2,744

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

59

54

Multifamily Real Estate [Member] | Commercial Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

284

491

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

12

20

Commercial and Industrial [Member] | Commercial Non Real Estate Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

887

962

1,326

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

22

25

27

Automobile Loan [Member] | Consumer Non Real Estate Portfolio Segment [Member]

Average recorded investment in impaired loans(1)

^[1]

$ 3

$ 3

20

^[2]

Income recognized on impaired loans, after designation as impaired

^[1]

$ 1

[1]	Only classes with impaired loans are shown.
[2]	Recorded investment is net of charge-offs and interest paid while a loan is in nonaccrual status.
[3]	Only classes with past due or nonaccrual loans are presented

X

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a 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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5258-111524

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were 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)(2)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5212-111524

+ Details

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- Details

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