Loans (Schedule for Loans Individually Evaluated for Impairment) (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
With No Related Allowance Recorded:
Unpaid Principal Balance	[1]	$ 3,878		$ 3,878		$ 3,936
Recorded Investment		3,646		3,646		3,410
Average Recorded Investment		3,655	$ 3,491	3,271	$ 2,173
Interest Income Recognized		40	26	92	82
Cash Basis Recognized		2	0	9	47
With An Allowance Recorded:
Unpaid Principal Balance	[1]	7,113		7,113		9,293
Recorded Investment		6,946		6,946		9,228
Allowance for Loan Losses Allocated		1,624		1,624		2,234
Average Recorded Investment		7,287	6,747	8,005	3,785
Interest Income Recognized		5	5	16	17
Cash Basis Recognized		9	1	9	8
Unpaid Principal Balance	[1]	10,991		10,991		13,229
Recorded Investment		10,592		10,592		12,638
Average Recorded Investment		10,942	10,238	11,276	5,958
Interest Income Recognized		45	31	108	99
Cash Basis Recognized		11	1	18	55
Loans Acquired With Deteriorated Credit Quality
With No Related Allowance Recorded:
Unpaid Principal Balance	[1]	1,194		1,194		1,255
Recorded Investment		1,003		1,003		797
Average Recorded Investment		995	771	697	826
Interest Income Recognized		11	0	11	25
Cash Basis Recognized		0	0	0	25
With An Allowance Recorded:
Unpaid Principal Balance	[1]	363		363		252
Recorded Investment		195		195		208
Allowance for Loan Losses Allocated		30		30		6
Average Recorded Investment		197	215	200	255
Interest Income Recognized		5	4	16	15
Cash Basis Recognized		0	0	0	7
Commercial and Industrial Loans and Leases
With No Related Allowance Recorded:
Unpaid Principal Balance	[1]	1,117		1,117		1,205
Recorded Investment		1,120		1,120		1,166
Average Recorded Investment		1,130	1,202	1,152	456
Interest Income Recognized		14	13	40	15
Cash Basis Recognized		2	0	2	2
With An Allowance Recorded:
Unpaid Principal Balance	[1]	2,400		2,400		4,804
Recorded Investment		2,400		2,400		4,763
Allowance for Loan Losses Allocated		208		208		1,402
Average Recorded Investment		2,594	2,865	3,189	1,011
Interest Income Recognized		1	2	2	4
Cash Basis Recognized		9	1	9	2
Commercial Real Estate Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	[1]	2,102		2,102		1,812
Recorded Investment		1,974		1,974		1,495
Average Recorded Investment		1,988	1,554	1,525	1,067
Interest Income Recognized		26	13	52	43
Cash Basis Recognized		0	0	7	29
With An Allowance Recorded:
Unpaid Principal Balance	[1]	4,713		4,713		4,489
Recorded Investment		4,546		4,546		4,465
Allowance for Loan Losses Allocated		1,416		1,416		832
Average Recorded Investment		4,693	3,654	4,816	2,290
Interest Income Recognized		4	3	14	13
Cash Basis Recognized		0	0	0	6
Agricultural Loans
With No Related Allowance Recorded:
Unpaid Principal Balance	[1]	659		659		919
Recorded Investment		552		552		749
Average Recorded Investment		537	735	594	650
Interest Income Recognized		0	0	0	24
Cash Basis Recognized		0	0	0	16
With An Allowance Recorded:
Unpaid Principal Balance	[1]	0		0		0
Recorded Investment		0		0		0
Allowance for Loan Losses Allocated		0		0		$ 0
Average Recorded Investment		0	228	0	484
Interest Income Recognized		0	0	0	0
Cash Basis Recognized		$ 0	$ 0	$ 0	$ 0

[1] Unpaid Principal Balance is the remaining contractual principal payments gross of partial charge-offs and discounts.