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Note 12 - Fair Value Measurements - Quantitative Information About Level 3 Fair Value Measurements (Details) - Impaired Loans [Member] - Fair Value, Nonrecurring [Member] $ in Thousands	Sep. 30, 2019 USD ($)	Dec. 31, 2018 USD ($)
Impaired loans, net	$ 476	$ 391
Fair Value, Inputs, Level 3 [Member]
Impaired loans, net	$ 476	$ 391
Fair Value, Inputs, Level 3 [Member] | Measurement Input, Discount Rate [Member]
Impaired loans, net, range (weighted average)	0.1	0.1

X

- Definition

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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

X

- Definition

Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

+ Details

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X

- Details

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- Details

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- Details

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- Details

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