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Note 5 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings Subsequently Defaulted (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2018 USD ($)	Dec. 31, 2017
Number of contracts, subsequently defaulted		0
Real Estate Mortgage Portfolio Segment [Member] | Residential Loan [Member]
Number of contracts, subsequently defaulted	1
Recorded investment, subsequently defaulted	$ 19

X

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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Balance Type:	na
Period Type:	duration

X

- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

+ Details

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Namespace Prefix:	us-gaap_
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Period Type:	duration

X

- Details

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Namespace Prefix:
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Balance Type:
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X

- Details

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Namespace Prefix:
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