Note 4 - Loans - Impaired Loan Balances by Portfolio Segment (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2020	Dec. 31, 2019
Recorded investment, with no related allowance recorded	$ 2,563	$ 1,203
Unpaid principal balance, with no related allowance recorded	2,568	1,202
Average recorded investment, with no related allowance recorded	1,761	1,137
Interest income recognized, with no related allowance recorded	79	88
Recorded investment, with a related allowance recorded	656	989
Unpaid principal balance, with a related allowance recorded	651	984
Related allowance	286	230
Average recorded investment, with a related allowance recorded	998	416
Interest income recognized, with a related allowance recorded	27	57
Recorded investment	3,219	2,192
Unpaid principal balance	3,219	2,186
Average recorded investment	2,759	1,553
Interest income recognized	106	145
Commercial Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	49
Unpaid principal balance, with no related allowance recorded	0	49
Average recorded investment, with no related allowance recorded	33	16
Interest income recognized, with no related allowance recorded	1	5
Recorded investment, with a related allowance recorded	149	735
Unpaid principal balance, with a related allowance recorded	144	730
Related allowance	122	204
Average recorded investment, with a related allowance recorded	574	191
Interest income recognized, with a related allowance recorded	13	41
Recorded investment	149	784
Unpaid principal balance	144	779
Average recorded investment	607	207
Interest income recognized	14	46
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land Development [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	0	0
Commercial Real Estate Portfolio Segment [Member] \| Commercial Real Estate [Member]
Recorded investment, with no related allowance recorded	1,620	502
Unpaid principal balance, with no related allowance recorded	1,617	500
Average recorded investment, with no related allowance recorded	866	424
Interest income recognized, with no related allowance recorded	53	39
Recorded investment, with a related allowance recorded	259	0
Unpaid principal balance, with a related allowance recorded	259	0
Related allowance	138	0
Average recorded investment, with a related allowance recorded	173	0
Interest income recognized, with a related allowance recorded	8	0
Recorded investment	1,879	502
Unpaid principal balance	1,876	500
Average recorded investment	1,039	424
Interest income recognized	61	39
Residential Portfolio Segment [Member] \| Residential [Member]
Recorded investment, with no related allowance recorded	900	611
Unpaid principal balance, with no related allowance recorded	908	612
Average recorded investment, with no related allowance recorded	821	652
Interest income recognized, with no related allowance recorded	22	38
Recorded investment, with a related allowance recorded	248	254
Unpaid principal balance, with a related allowance recorded	248	254
Related allowance	26	26
Average recorded investment, with a related allowance recorded	251	225
Interest income recognized, with a related allowance recorded	6	16
Recorded investment	1,148	865
Unpaid principal balance	1,156	866
Average recorded investment	1,072	877
Interest income recognized	28	54
Residential Portfolio Segment [Member] \| Home Equity Line of Credit [Member]
Recorded investment, with no related allowance recorded	43	41
Unpaid principal balance, with no related allowance recorded	43	41
Average recorded investment, with no related allowance recorded	41	45
Interest income recognized, with no related allowance recorded	3	6
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	43	41
Unpaid principal balance	43	41
Average recorded investment	41	45
Interest income recognized	3	6
Consumer Portfolio Segment [Member]
Recorded investment, with no related allowance recorded	0	0
Unpaid principal balance, with no related allowance recorded	0	0
Average recorded investment, with no related allowance recorded	0	0
Interest income recognized, with no related allowance recorded	0	0
Recorded investment, with a related allowance recorded	0	0
Unpaid principal balance, with a related allowance recorded	0	0
Related allowance	0	0
Average recorded investment, with a related allowance recorded	0	0
Interest income recognized, with a related allowance recorded	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment	0	0
Interest income recognized	$ 0	$ 0

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

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

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