Loans (Allowance for Credit Losses on Financing Receivables) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Allowance for loan losses:
Beginning Balance	$ 10,976	$ 10,515
Charge-offs	(742)	(580)
Recoveries	112	36
Provisions	500	500
Ending Balance	10,846	10,471
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	6,882	6,451
Charge-offs		(236)
Recoveries	2	2
Provisions	(142)	447
Ending Balance	6,742	6,664
Residential First Mortgages Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	755	1,144
Charge-offs		(37)
Provisions	(33)	(170)
Ending Balance	722	937
Residential Rentals Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	498	512
Charge-offs	(53)
Recoveries	46
Provisions	(29)	(53)
Ending Balance	462	459
Construction And Land Development Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	310	462
Provisions	(162)	20
Ending Balance	148	482
Home Equity And Second Mortgage Loans [Member]
Allowance for loan losses:
Beginning Balance	133	162
Charge-offs		(7)
Recoveries	2	9
Provisions	(3)	(46)
Ending Balance	132	118
Commercial Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	1,482	1,013
Recoveries	5
Provisions	(81)	32
Ending Balance	1,406	1,045
Consumer Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	6	7
Charge-offs	(4)	(1)
Recoveries	1
Provisions	5	1
Ending Balance	8	7
Commercial Equipment Portfolio Segment [Member]
Allowance for loan losses:
Beginning Balance	910	764
Charge-offs	(685)	(299)
Recoveries	56	25
Provisions	945	269
Ending Balance	$ 1,226	$ 759

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

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

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- References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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