Note 5 - Loans - Impaired Financing Receivable (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Related allowance	$ 34	$ 179
Principal balance with no related allowance	1,548	2,072
Recorded investment with no related allowance	1,473	1,974
Average investment with no related allowance	1,527	2,936
Interest recognized with no related allowance	14	25
Principal balance	1,650	2,447
Recorded investment	1,572	2,304
Average investment	1,628	3,248
Interest recognized	14	33
Residential Real Estate and Consumer [Member] \| One to Four Family Investor-owned [Member]
Principal balance with related allowance	102	375
Recorded investment with related allowance	99	330
Related allowance	34	179
Average investment with related allowance	101	312
Interest recognized with related allowance		8
Principal balance with no related allowance	250	716
Recorded investment with no related allowance	250	683
Average investment with no related allowance	250	1,289
Interest recognized with no related allowance		24
Residential Real Estate and Consumer [Member] \| One to Four Family Owner-occupied [Member]
Principal balance with no related allowance	1,205	1,158
Recorded investment with no related allowance	1,132	1,099
Average investment with no related allowance	1,182	1,443
Interest recognized with no related allowance	12	1
Residential Real Estate and Consumer [Member] \| Consumer [Member]
Principal balance with no related allowance	18
Recorded investment with no related allowance	18
Average investment with no related allowance	19
Interest recognized with no related allowance
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Principal balance with no related allowance	75	198
Recorded investment with no related allowance	73	192
Average investment with no related allowance	76	204
Interest recognized with no related allowance	$ 2

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)
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