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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Impaired Loans, Average Investment and Interest Income (Details) - USD ($)
$ in Thousands

6 Months Ended

12 Months Ended

Jun. 30, 2018

Jun. 30, 2017

Dec. 31, 2017

Average recorded investment in impaired loans(1)

^[1],[2]

$ 12,326

$ 12,017

$ 13,344

^[3]

Interest income recognized on impaired loans, after designation as impaired

239

192

528

^[3]

Real Estate Construction Portfolio Segment[Member] | Construction, 1-4 Family Residential [Member]

Average recorded investment in impaired loans(1)

^[2],[3]

2,788

3,335

3,298

Interest income recognized on impaired loans, after designation as impaired

^[3]

74

89

177

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

Average recorded investment in impaired loans(1)

^[2],[3]

667

603

781

Interest income recognized on impaired loans, after designation as impaired

^[3]

15

18

57

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

Average recorded investment in impaired loans(1)

^[2],[3]

167

190

185

Interest income recognized on impaired loans, after designation as impaired

^[3]

5

6

11

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

Average recorded investment in impaired loans(1)

^[2],[3]

317

335

329

Interest income recognized on impaired loans, after designation as impaired

^[3]

8

2

1

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

Average recorded investment in impaired loans(1)

^[2],[3]

301

887

748

Interest income recognized on impaired loans, after designation as impaired

^[3]

8

16

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

Average recorded investment in impaired loans(1)

^[2],[3]

4,007

3,777

4,047

Interest income recognized on impaired loans, after designation as impaired

^[3]

98

77

200

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

Average recorded investment in impaired loans(1)

^[2],[3]

2,852

2,681

2,638

Interest income recognized on impaired loans, after designation as impaired

^[3]

11

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

Average recorded investment in impaired loans(1)

^[2],[3]

1,201

207

1,282

Interest income recognized on impaired loans, after designation as impaired

^[3]

19

64

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

Average recorded investment in impaired loans(1)

^[2]

26

^[3]

2

36

Interest income recognized on impaired loans, after designation as impaired

$ 1

^[3]

$ 0

$ 2

^[3]

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

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=84173941&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=84173941&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=84173941&loc=d3e5212-111524

+ Details

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X

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- Details

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