Note 15 - Assets and Liabilities Measured and Reported at Fair Value - Significant Unobservable Inputs (Details) - Fair Value, Inputs, Level 3 [Member] - Appraisal Discount Method [Member]	Mar. 31, 2018 USD ($)
Impaired loans - collateral dependent, fair value	$ 5,918
Other real estate owned, fair value	$ 360
Weighted Average [Member]
Impaired loans - collateral dependent, weighted average of input	42.2
Other real estate owned, weighted average of input	10

Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

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=99377789&loc=d3e19207-110258

Name:	us-gaap_OtherRealEstateOwnedMeasurementInput
Namespace Prefix:	us-gaap_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	instant