Loans Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Recorded Investment:
With No Related Allowance	$ 1,374	$ 1,778	$ 2,144
With a Related Allowance		288	1,543
Unpaid Principal Balance:
With No Related Allowance	1,377	1,778	2,185
With a Related Allowance	1,582	288	1,498
Average Recorded Balance:
With No Related Allowance	1,760	1,929
With a Related Allowance	1,583	144
Interest Income Recognized:
With No Related Allowance	16	1
With a Related Allowance	24	0
Cash Basis Income:
With No Related Allowance	0	0
With a Related Allowance	0	0
Commercial
Recorded Investment:
With No Related Allowance	0	0	0
With a Related Allowance	483	0	485
Unpaid Principal Balance:
With No Related Allowance	0	0	0
With a Related Allowance	489	0	489
Average Recorded Balance:
With No Related Allowance	0	0
With a Related Allowance	484	0
Interest Income Recognized:
With No Related Allowance	0	0
With a Related Allowance	0	0
Cash Basis Income:
With No Related Allowance	0	0
With a Related Allowance	0	0
Commercial Real Estate Portfolio Segment
Recorded Investment:
With No Related Allowance	8	884	781
With a Related Allowance	783	0	725
Unpaid Principal Balance:
With No Related Allowance	8	884	816
With a Related Allowance	807	0	721
Average Recorded Balance:
With No Related Allowance	395	887
With a Related Allowance	754	0
Interest Income Recognized:
With No Related Allowance	0	0
With a Related Allowance	0	0
Cash Basis Income:
With No Related Allowance	0	0
With a Related Allowance	0	0
Consumer Portfolio Segment
Recorded Investment:
With No Related Allowance	90	88	94
With a Related Allowance	0	0	0
Unpaid Principal Balance:
With No Related Allowance	90	88	95
With a Related Allowance	0	0	0
Average Recorded Balance:
With No Related Allowance	92	90
With a Related Allowance	0	0
Interest Income Recognized:
With No Related Allowance	0	1
With a Related Allowance	0	0
Cash Basis Income:
With No Related Allowance	0	0
With a Related Allowance	0	0
Residential
Recorded Investment:
With No Related Allowance	1,276	806	1,269
With a Related Allowance	356	288	333
Unpaid Principal Balance:
With No Related Allowance	1,279	806	1,274
With a Related Allowance	286	288	$ 288
Average Recorded Balance:
With No Related Allowance	1,273	952
With a Related Allowance	345	144
Interest Income Recognized:
With No Related Allowance	16	0
With a Related Allowance	24	0
Cash Basis Income:
With No Related Allowance	0	0
With a Related Allowance	$ 0	$ 0

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Reference 1: 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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