Note D - Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Balance	$ 7,699	$ 6,648	$ 8,334
Provision for loan losses	2,564	2,826	1,090
Loans charged off	(4,081)	(3,203)	(4,251)
Recoveries	1,317	1,428	1,475
Balance	7,499	7,699	6,648
Residential Portfolio Segment [Member]
Balance	939	1,087	1,426
Provision for loan losses	1,016	(63)	103
Loans charged off	(745)	(384)	(828)
Recoveries	260	299	386
Balance	1,470	939	1,087
Commercial Real Estate Portfolio Segment [Member]
Balance	4,315	1,959	4,195
Provision for loan losses	(632)	2,287	(469)
Loans charged off	(1,067)	(63)	(1,971)
Recoveries	362	132	204
Balance	2,978	4,315	1,959
Commercial and Industrial Portfolio Segment [Member]
Balance	907	2,589	1,602
Provision for loan losses	658	(1,112)	777
Loans charged off	(627)	(586)	(24)
Recoveries	86	16	234
Balance	1,024	907	2,589
Consumer Portfolio Segment [Member]
Balance	1,538	1,013	1,111
Provision for loan losses	1,522	1,714	679
Loans charged off	(1,642)	(2,170)	(1,428)
Recoveries	609	981	651
Balance	$ 2,027	$ 1,538	$ 1,013

A valuation allowance for financing receivables that are expected to be uncollectible.

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

+ Details

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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