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Note 3 - Loans and Allowance for Loan Losses - Impaired Loans (Details) - USD ($)	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2021
With no related allowance recorded, unpaid principal balance		$ 16,997,000
With no related allowance recorded, principal balance		15,715,000
With no related allowance recorded, average recorded principal balance	$ 22,826,000
With related allowance recorded, unpaid principal balance		3,671,000
With related allowance recorded, principal balance		3,651,000
Related allowance		546,000
With related allowance recorded, average recorded principal balance	2,069,000
Total unpaid principal balance		20,668,000
Total principal balance		19,366,000
Total average recorded principal balance	24,895,000
Commercial Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance		12,658,000
With no related allowance recorded, principal balance		12,583,000
With no related allowance recorded, average recorded principal balance	19,313,000
With related allowance recorded, unpaid principal balance		3,099,000
With related allowance recorded, principal balance		3,099,000
Related allowance		354,000
With related allowance recorded, average recorded principal balance	1,137,000
Total unpaid principal balance		15,757,000
Total principal balance		15,682,000
Total average recorded principal balance	20,450,000
Commercial Portfolio Segment [Member] | Commercial and Industrial [Member]
With no related allowance recorded, unpaid principal balance		2,893,000
With no related allowance recorded, principal balance		2,818,000
With no related allowance recorded, average recorded principal balance	4,913,000
With related allowance recorded, unpaid principal balance		2,192,000
With related allowance recorded, principal balance		2,192,000
Related allowance		266,000
With related allowance recorded, average recorded principal balance	345,000
Commercial Portfolio Segment [Member] | Vacant Land and Land Development and Residential Construction Loan [Member]
With no related allowance recorded, unpaid principal balance		0
With no related allowance recorded, principal balance		0
With no related allowance recorded, average recorded principal balance	0
With related allowance recorded, unpaid principal balance		0
With related allowance recorded, principal balance		0
Related allowance		0
With related allowance recorded, average recorded principal balance	0
Commercial Portfolio Segment [Member] | Real Estate Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance		9,674,000
With no related allowance recorded, principal balance		9,674,000
With no related allowance recorded, average recorded principal balance	14,074,000
With related allowance recorded, unpaid principal balance		761,000
With related allowance recorded, principal balance		761,000
Related allowance		84,000
With related allowance recorded, average recorded principal balance	632,000
Commercial Portfolio Segment [Member] | Real Estate Non Owner Occupied Loan [Member]
With no related allowance recorded, unpaid principal balance		0
With no related allowance recorded, principal balance		0
With no related allowance recorded, average recorded principal balance	326,000
With related allowance recorded, unpaid principal balance		146,000
With related allowance recorded, principal balance		146,000
Related allowance		4,000
With related allowance recorded, average recorded principal balance	160,000
Commercial Portfolio Segment [Member] | Real Estate Multi Family and Residential Rental Loan [Member]
With no related allowance recorded, unpaid principal balance		91,000
With no related allowance recorded, principal balance		91,000
With no related allowance recorded, average recorded principal balance	0
With related allowance recorded, unpaid principal balance		0
With related allowance recorded, principal balance		0
Related allowance		0
With related allowance recorded, average recorded principal balance	0
Retail Portfolio Segment [Member]
With no related allowance recorded, unpaid principal balance		4,339,000
With no related allowance recorded, principal balance		3,132,000
With no related allowance recorded, average recorded principal balance	3,513,000
With related allowance recorded, unpaid principal balance		572,000
With related allowance recorded, principal balance		552,000
Related allowance		192,000
With related allowance recorded, average recorded principal balance	932,000
Total unpaid principal balance		4,911,000
Total principal balance		3,684,000
Total average recorded principal balance	4,445,000
Retail Portfolio Segment [Member] | Home Equity and Other [Member]
With no related allowance recorded, unpaid principal balance		1,173,000
With no related allowance recorded, principal balance		1,107,000
With no related allowance recorded, average recorded principal balance	963,000
With related allowance recorded, unpaid principal balance		160,000
With related allowance recorded, principal balance		140,000
Related allowance		123,000
With related allowance recorded, average recorded principal balance	267,000
Retail Portfolio Segment [Member] | One to Four Family Mortgages [Member]
With no related allowance recorded, unpaid principal balance		3,166,000
With no related allowance recorded, principal balance		2,205,000
With no related allowance recorded, average recorded principal balance	2,550,000
With related allowance recorded, unpaid principal balance		412,000
With related allowance recorded, principal balance		412,000
Related allowance		$ 69,000
With related allowance recorded, average recorded principal balance	$ 665,000

X

- Definition

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

+ References

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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-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
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