Loans, Receivables Past Due (Details) - USD ($) $ in Thousands		Mar. 31, 2019	Dec. 31, 2018
Non performing loans [Abstract]
90+ and Still Accruing		$ 0	$ 5
Non-Accrual		8,849	9,029
Total Non-performing Loans		8,849	9,034
Accrued interest included in recorded investment		0	0
Aging analysis of loans by class [Abstract]
Total		13,114	12,795
Loans not Past Due		2,614,464	2,578,263
Total loans recorded investment		2,627,578	2,591,058
Accrued interest included in recorded investment		8,783	8,538
Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		4,634	4,960
Accrued interest included in recorded investment		63	44
Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		1,151	820
Accrued interest included in recorded investment		19	11
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		7,329	7,015
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		82	55
Loans Not Past Due [Member]
Aging analysis of loans by class [Abstract]
Accrued interest included in recorded investment		8,701	8,483
Commercial [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		1,171,841	1,147,892
Accrued interest included in recorded investment		3,437	3,411
Commercial [Member] | Income Producing - Real Estate [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		0	44
Loans not Past Due		398,191	388,729
Total loans recorded investment		398,191	388,773
Commercial [Member] | Income Producing - Real Estate [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	44
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	0
Commercial [Member] | Land, Land Development and Construction - Real Estate [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		0	0
Loans not Past Due		84,861	84,458
Total loans recorded investment		84,861	84,458
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	0
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		1,705	2,220
Total Non-performing Loans		1,705	2,220
Aging analysis of loans by class [Abstract]
Total		45	1,538
Loans not Past Due		688,744	673,123
Total loans recorded investment		688,789	674,661
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		40	1,538
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	0
Commercial [Member] | Commercial and Industrial [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		5	0
Mortgage [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		1,048,007	1,046,987
Accrued interest included in recorded investment	[1]	4,262	4,097
Mortgage [Member] | 1-4 Family [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	5
Non-Accrual		4,878	4,695
Total Non-performing Loans		4,878	4,700
Aging analysis of loans by class [Abstract]
Total		9,186	6,684
Loans not Past Due		803,882	833,760
Total loans recorded investment		813,068	840,444
Accrued interest included in recorded investment	[1]	3,220	3,079
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		3,295	1,608
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		833	194
Mortgage [Member] | 1-4 Family [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		5,058	4,882
Mortgage [Member] | Resort Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		508	755
Total Non-performing Loans		508	755
Aging analysis of loans by class [Abstract]
Total		913	1,007
Loans not Past Due		77,315	80,774
Total loans recorded investment		78,228	81,781
Accrued interest included in recorded investment	[1]	386	363
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		321	252
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		84	0
Mortgage [Member] | Resort Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		508	755
Mortgage [Member] | Home Equity - 1st Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		157	159
Total Non-performing Loans		157	159
Aging analysis of loans by class [Abstract]
Total		273	335
Loans not Past Due		36,966	38,909
Total loans recorded investment		37,239	39,244
Accrued interest included in recorded investment	[1]	177	199
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		99	176
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		17	0
Mortgage [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		157	159
Mortgage [Member] | Home Equity - 2nd Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		573	419
Total Non-performing Loans		573	419
Aging analysis of loans by class [Abstract]
Total		896	965
Loans not Past Due		118,576	84,553
Total loans recorded investment		119,472	85,518
Accrued interest included in recorded investment	[1]	479	456
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		228	446
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		95	100
Mortgage [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		573	419
Installment [Member]
Aging analysis of loans by class [Abstract]
Total loans recorded investment		407,730	396,179
Accrued interest included in recorded investment	[1]	1,084	1,030
Installment [Member] | Home Equity - 1st Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		219	178
Total Non-performing Loans		219	178
Aging analysis of loans by class [Abstract]
Total		257	452
Loans not Past Due		6,631	6,985
Total loans recorded investment		6,888	7,437
Accrued interest included in recorded investment	[1]	26	28
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		36	200
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		2	55
Installment [Member] | Home Equity - 1st Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		219	197
Installment [Member] | Home Equity - 2nd Lien [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		234	226
Total Non-performing Loans		234	226
Aging analysis of loans by class [Abstract]
Total		384	361
Loans not Past Due		6,043	6,683
Total loans recorded investment		6,427	7,044
Accrued interest included in recorded investment	[1]	21	25
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		150	111
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	24
Installment [Member] | Home Equity - 2nd Lien [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		234	226
Installment [Member] | Boat Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		359	166
Total Non-performing Loans		359	166
Aging analysis of loans by class [Abstract]
Total		584	777
Loans not Past Due		175,005	169,117
Total loans recorded investment		175,589	169,894
Accrued interest included in recorded investment	[1]	437	403
Installment [Member] | Boat Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		206	316
Installment [Member] | Boat Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		19	295
Installment [Member] | Boat Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		359	166
Installment [Member] | Recreational Vehicle Lending [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		6	7
Total Non-performing Loans		6	7
Aging analysis of loans by class [Abstract]
Total		82	56
Loans not Past Due		130,016	125,780
Total loans recorded investment		130,098	125,836
Accrued interest included in recorded investment	[1]	333	311
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		76	28
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		0	21
Installment [Member] | Recreational Vehicle Lending [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		6	7
Installment [Member] | Other [Member]
Non performing loans [Abstract]
90+ and Still Accruing		0	0
Non-Accrual		210	204
Total Non-performing Loans		210	204
Aging analysis of loans by class [Abstract]
Total		494	576
Loans not Past Due		88,234	85,392
Total loans recorded investment		88,728	85,968
Accrued interest included in recorded investment	[1]	267	263
Installment [Member] | Other [Member] | Loans Past Due, 30-59 days [Member]
Aging analysis of loans by class [Abstract]
Total		183	241
Installment [Member] | Other [Member] | Loans Past Due, 60-89 days [Member]
Aging analysis of loans by class [Abstract]
Total		101	131
Installment [Member] | Other [Member] | Loans Past Due, 90+ days [Member]
Aging analysis of loans by class [Abstract]
Total		$ 210	$ 204

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