Loans Impaired Loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Recorded Investment:
With No Related Allowance	$ 1,825	$ 1,773	$ 1,825	$ 1,773	$ 2,144
With a Related Allowance	1,622	1,502	1,622	1,502	1,543
Unpaid Principal Balance:
With No Related Allowance	1,847	1,758	1,847	1,758	2,185
With a Related Allowance	1,576	1,500	1,576	1,500	1,498
Average Recorded Balance:
With No Related Allowance	1,482	1,921	1,985	1,927
With a Related Allowance	1,622	1,147	1,583	752
Interest Income Recognized:
With No Related Allowance	0	1	0	3
With a Related Allowance	0	0	20	4
Cash Basis Income:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Commercial
Recorded Investment:
With No Related Allowance	0	0	0	0	0
With a Related Allowance	475	489	475	489	485
Unpaid Principal Balance:
With No Related Allowance	0	0	0	0	0
With a Related Allowance	489	489	489	489	489
Average Recorded Balance:
With No Related Allowance	0	0	0	0
With a Related Allowance	478	496	480	245
Interest Income Recognized:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Cash Basis Income:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Commercial Real Estate Portfolio Segment
Recorded Investment:
With No Related Allowance	5	818	5	818	781
With a Related Allowance	801	725	801	725	725
Unpaid Principal Balance:
With No Related Allowance	5	818	5	818	816
With a Related Allowance	807	723	807	723	721
Average Recorded Balance:
With No Related Allowance	7	998	393	854
With a Related Allowance	794	363	763	363
Interest Income Recognized:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Cash Basis Income:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Consumer Portfolio Segment
Recorded Investment:
With No Related Allowance	108	104	108	104	94
With a Related Allowance	0	0	0	0	0
Unpaid Principal Balance:
With No Related Allowance	109	90	109	90	95
With a Related Allowance	0	0	0	0	0
Average Recorded Balance:
With No Related Allowance	104	96	101	98
With a Related Allowance	0	0	0	0
Interest Income Recognized:
With No Related Allowance	0	1	0	3
With a Related Allowance	0	0	0	0
Cash Basis Income:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	0	0
Residential
Recorded Investment:
With No Related Allowance	1,712	851	1,712	851	1,269
With a Related Allowance	346	288	346	288	333
Unpaid Principal Balance:
With No Related Allowance	1,733	850	1,733	850	1,274
With a Related Allowance	280	288	280	288	$ 288
Average Recorded Balance:
With No Related Allowance	1,371	827	1,491	975
With a Related Allowance	350	288	340	144
Interest Income Recognized:
With No Related Allowance	0	0	0	0
With a Related Allowance	0	0	20	4
Cash Basis Income:
With No Related Allowance	0	0	0	0
With a Related Allowance	$ 0	$ 0	$ 0	$ 0

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