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Note 8 - Loans and Related Allowance for Loan and Lease Losses - Troubled Debt Restructurings Subsequently Defaulted (Details) - Real Estate Mortgage Portfolio Segment [Member] - Residential Loan [Member]	6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)
Number of contracts, subsequently defaulted	2	1
Recorded investment, subsequently defaulted	$ 215,000	$ 33,000

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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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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Period Type:	duration

X

- Details

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Namespace Prefix:
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X

- Details

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Namespace Prefix:
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