Loans (Impaired Financing Receivables) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Unpaid contractual principal balance	$ 43,618	$ 36,685
Recorded investment with no allowance	39,028	26,436
Recorded investment with allowance	4,226	8,924
Total recorded investment	43,254	35,360
Related allowance	1,024	1,289
Average recorded investment	44,159	36,534
Interest income recognized	1,829	1,309
Commercial Real Estate Portfolio Segment [Member]
Unpaid contractual principal balance	33,180	22,195
Recorded investment with no allowance	30,921	14,896
Recorded investment with allowance	2,008	7,081
Total recorded investment	32,929	21,977
Related allowance	370	806
Average recorded investment	33,575	22,303
Interest income recognized	1,379	908
Residential First Mortgages Portfolio Segment [Member]
Unpaid contractual principal balance	2,455	2,436
Recorded investment with no allowance	1,978	1,938
Recorded investment with allowance	459	475
Total recorded investment	2,437	2,413
Related allowance	2	7
Average recorded investment	2,479	2,445
Interest income recognized	91	90
Residential Rentals Portfolio Segment [Member]
Unpaid contractual principal balance	2,389	3,440
Recorded investment with no allowance	1,981	2,850
Recorded investment with allowance	395	178
Total recorded investment	2,376	3,028
Related allowance	18	36
Average recorded investment	2,432	3,486
Interest income recognized	111	134
Construction And Land Development Portfolio Segment [Member]
Unpaid contractual principal balance	729	4,304
Recorded investment with no allowance		2,926
Recorded investment with allowance	729	851
Total recorded investment	729	3,777
Related allowance	163	178
Average recorded investment	729	3,867
Interest income recognized	26	16
Home Equity And Second Mortgages Portfolio Segment [Member]
Unpaid contractual principal balance	317	170
Recorded investment with no allowance	317	170
Total recorded investment	317	170
Average recorded investment	318	176
Interest income recognized	12	7
Commercial Portfolio Segment [Member]
Unpaid contractual principal balance	3,010	3,285
Recorded investment with no allowance	2,783	3,004
Recorded investment with allowance	168	200
Total recorded investment	2,951	3,204
Related allowance	168	123
Average recorded investment	3,048	3,442
Interest income recognized	137	137
Commercial Equipment Portfolio Segment [Member]
Unpaid contractual principal balance	1,538	855
Recorded investment with no allowance	1,048	652
Recorded investment with allowance	467	139
Total recorded investment	1,515	791
Related allowance	303	139
Average recorded investment	1,578	815
Interest income recognized	$ 73	$ 17

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5258-111524

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953550-111524

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