Loans, Receivables Past Due (Details) - USD ($) $ in Thousands		Mar. 31, 2018	Dec. 31, 2017
Non performing loans [Abstract]
90+ and Still Accruing		$ 0	$ 0
Non-Accrual		6,629	8,184
Total Non-performing Loans		6,629	8,184
Accrued interest included in recorded investment		0	0
Aging analysis of loans by class [Abstract]
Total		11,081	12,554
Loans not Past Due		2,066,816	2,012,764
Total loans recorded investment		2,077,897	2,025,318
Accrued interest included in recorded investment		6,462	6,501
Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		3,769	3,671
Accrued interest included in recorded investment		46	43
Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		1,122	1,271
Accrued interest included in recorded investment		17	22
Loans Past Due, 90+ days [Member]
Non performing loans [Abstract]
Accrued interest included in recorded investment		0	0
Aging analysis of loans by class [Abstract]
Total		6,190	7,612
Accrued interest included in recorded investment		0	0
Loans Past Due Total [Member]
Aging analysis of loans by class [Abstract]
Accrued interest included in recorded investment		63	65
Loans Not Past Due [Member]
Aging analysis of loans by class [Abstract]
Accrued interest included in recorded investment		6,399	6,436
Commercial [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		859,686	855,560
Accrued interest included in recorded investment		2,269	2,300
Commercial [Member] | Income Producing - Real Estate [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		0	30
Total Non-performing Loans		0	30
Aging analysis of loans by class [Abstract]
Total		0	30
Loans not Past Due		304,709	290,466
Total loans recorded investment		304,709	290,496
Commercial [Member] | Income Producing - Real Estate [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Commercial [Member] | Income Producing - Real Estate [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Commercial [Member] | Income Producing - Real Estate [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		0	30
Commercial [Member] | Land, Land Development and Construction - Real Estate [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		0	9
Total Non-performing Loans		0	9
Aging analysis of loans by class [Abstract]
Total		0	9
Loans not Past Due		51,382	70,182
Total loans recorded investment		51,382	70,191
Commercial [Member] | Land, Land Development and Construction - Real Estate [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	9
Commercial [Member] | Land, Land Development and Construction - Real Estate [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Commercial [Member] | Land, Land Development and Construction - Real Estate [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Commercial [Member] | Commercial and Industrial [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		439	607
Total Non-performing Loans		439	607
Aging analysis of loans by class [Abstract]
Total		49	104
Loans not Past Due		503,546	494,769
Total loans recorded investment		503,595	494,873
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		41	60
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		8	0
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		0	44
Mortgage [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		892,226	852,808
Accrued interest included in recorded investment	[1]	3,316	3,278
Mortgage [Member] | 1-4 Family [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		4,213	5,130
Total Non-performing Loans		4,213	5,130
Aging analysis of loans by class [Abstract]
Total		7,254	7,484
Loans not Past Due		665,487	625,638
Total loans recorded investment		672,741	633,122
Accrued interest included in recorded investment	[1]	2,400	2,361
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		2,598	1,552
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		443	802
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		4,213	5,130
Mortgage [Member] | Resort Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		762	1,223
Total Non-performing Loans		762	1,223
Aging analysis of loans by class [Abstract]
Total		847	1,936
Loans not Past Due		86,582	88,620
Total loans recorded investment		87,429	90,556
Accrued interest included in recorded investment	[1]	370	371
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		85	713
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		762	1,223
Mortgage [Member] | Home Equity - 1st Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		309	326
Total Non-performing Loans		309	326
Aging analysis of loans by class [Abstract]
Total		634	672
Loans not Past Due		37,191	34,689
Total loans recorded investment		37,825	35,361
Accrued interest included in recorded investment	[1]	165	157
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		61	308
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		264	38
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		309	326
Mortgage [Member] | Home Equity - 2nd Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		301	316
Total Non-performing Loans		301	316
Aging analysis of loans by class [Abstract]
Total		889	824
Loans not Past Due		59,598	58,834
Total loans recorded investment		60,487	59,658
Accrued interest included in recorded investment	[1]	283	294
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		334	353
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		254	155
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		301	316
Mortgage [Member] | Purchased Loans [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		0	0
Total Non-performing Loans		0	0
Aging analysis of loans by class [Abstract]
Total		10	7
Loans not Past Due		33,734	34,104
Total loans recorded investment		33,744	34,111
Accrued interest included in recorded investment	[1]	98	95
Mortgage [Member] | Purchased Loans [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		9	7
Mortgage [Member] | Purchased Loans [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		1	0
Mortgage [Member] | Purchased Loans [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Installment [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		325,985	316,950
Accrued interest included in recorded investment	[1]	877	923
Installment [Member] | Home Equity - 1st Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		150	141
Total Non-performing Loans		150	141
Aging analysis of loans by class [Abstract]
Total		324	242
Loans not Past Due		8,497	9,213
Total loans recorded investment		8,821	9,455
Accrued interest included in recorded investment	[1]	32	39
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		174	90
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	11
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		150	141
Installment [Member] | Home Equity - 2nd Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		241	159
Total Non-performing Loans		241	159
Aging analysis of loans by class [Abstract]
Total		457	470
Loans not Past Due		8,411	9,001
Total loans recorded investment		8,868	9,471
Accrued interest included in recorded investment	[1]	38	43
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		157	217
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		59	94
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		241	159
Installment [Member] | Boat Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		66	100
Total Non-performing Loans		66	100
Aging analysis of loans by class [Abstract]
Total		230	195
Loans not Past Due		134,383	129,777
Total loans recorded investment		134,613	129,972
Accrued interest included in recorded investment	[1]	331	346
Installment [Member] | Boat Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		156	59
Installment [Member] | Boat Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		8	36
Installment [Member] | Boat Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		66	100
Installment [Member] | Recreational Vehicle Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		14	25
Total Non-performing Loans		14	25
Aging analysis of loans by class [Abstract]
Total		68	73
Loans not Past Due		98,489	92,737
Total loans recorded investment		98,557	92,810
Accrued interest included in recorded investment	[1]	248	254
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		30	28
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		24	20
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		14	25
Installment [Member] | Other [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		134	118
Total Non-performing Loans		134	118
Aging analysis of loans by class [Abstract]
Total		319	508
Loans not Past Due		74,807	74,734
Total loans recorded investment		75,126	75,242
Accrued interest included in recorded investment	[1]	228	241
Installment [Member] | Other [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		124	275
Installment [Member] | Other [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		61	115
Installment [Member] | Other [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		$ 134	$ 118

[1] Credit scores have been updated within the last twelve months.