Loans, Impaired Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Impaired loans with no allocated allowance for loan losses [Abstract]
Troubled debt restructurings ("TDR")	$ 317		$ 0
Non - TDR	798		0
Impaired loans with an allocated allowance for loan losses [Abstract]
TDR - allowance based on collateral	2,103		2,787
TDR - allowance based on present value cash flow	50,940		53,258
Non - TDR - allowance based on collateral	3,353		2,145
Total impaired loans	57,511		58,190
Amount of allowance for loan losses allocated [Abstract]
TDR - allowance based on collateral	472		769
TDR - allowance based on present value cash flow	4,944		4,849
Non - TDR - allowance based on collateral	1,270		692
Total amount of allowance for loan losses allocated	6,686		6,310
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	355		4
Unpaid Principal Balance, with no related allowance for loan losses recorded	708		616
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	57,411		58,457
Unpaid Principal Balance, with an allowance for loan losses recorded	60,401		60,282
Recorded Investment	57,766		58,461
Unpaid Principal Balance	61,109		60,898
Related Allowance	6,686		6,310
Accrued interest included in recorded investment	255		271
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	180	$ 540
Interest Income Recognized, with no related allowance for loan losses recorded	0	12
Average Recorded Investment, with an allowance for loan losses recorded	57,938	64,271
Interest Income Recognized, with an allowance for loan losses recorded	765	791
Average Recorded Investment	58,118	64,811
Interest Income Recognized	765	803
Commercial [Member] | Income Producing - Real Estate [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	4,720		4,770
Unpaid Principal Balance, with an allowance for loan losses recorded	4,712		4,758
Recorded Investment	4,720		4,770
Unpaid Principal Balance	4,712		4,758
Related Allowance	423		303
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	4,745	5,187
Interest Income Recognized, with an allowance for loan losses recorded	65	68
Average Recorded Investment	4,745	5,187
Interest Income Recognized	65	68
Commercial [Member] | Land, Land Development and Construction - Real Estate [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	290		290
Unpaid Principal Balance, with an allowance for loan losses recorded	288		289
Recorded Investment	290		290
Unpaid Principal Balance	288		289
Related Allowance	31		35
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	290	161
Interest Income Recognized, with an allowance for loan losses recorded	2	2
Average Recorded Investment	290	161
Interest Income Recognized	2	2
Commercial [Member] | Commercial and Industrial [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	2,918		3,637
Unpaid Principal Balance, with an allowance for loan losses recorded	3,175		3,735
Recorded Investment	2,918		3,637
Unpaid Principal Balance	3,175		3,735
Related Allowance	750		967
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	520
Interest Income Recognized, with no related allowance for loan losses recorded	0	4
Average Recorded Investment, with an allowance for loan losses recorded	3,278	2,517
Interest Income Recognized, with an allowance for loan losses recorded	20	32
Average Recorded Investment	3,278	3,037
Interest Income Recognized	20	36
Mortgage [Member] | 1-4 Family [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	355		3
Unpaid Principal Balance, with no related allowance for loan losses recorded	670		474
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	32,317		32,842
Unpaid Principal Balance, with an allowance for loan losses recorded	34,514		34,427
Recorded Investment	32,672		32,845
Unpaid Principal Balance	35,184		34,901
Related Allowance	3,648		2,859
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	179	19
Interest Income Recognized, with no related allowance for loan losses recorded	0	6
Average Recorded Investment, with an allowance for loan losses recorded	32,580	36,367
Interest Income Recognized, with an allowance for loan losses recorded	446	458
Average Recorded Investment	32,759	36,386
Interest Income Recognized	446	464
Mortgage [Member] | Resort Lending [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	12,967		13,328
Unpaid Principal Balance, with an allowance for loan losses recorded	13,179		13,354
Recorded Investment	12,967		13,328
Unpaid Principal Balance	13,179		13,354
Related Allowance	1,366		1,927
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	13,148	15,779
Interest Income Recognized, with an allowance for loan losses recorded	175	164
Average Recorded Investment	13,148	15,779
Interest Income Recognized	175	164
Mortgage [Member] | Home Equity - 1st Lien [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	118		65
Unpaid Principal Balance, with an allowance for loan losses recorded	119		64
Recorded Investment	118		65
Unpaid Principal Balance	119		64
Related Allowance	23		4
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	92	164
Interest Income Recognized, with an allowance for loan losses recorded	1	2
Average Recorded Investment	92	164
Interest Income Recognized	1	2
Mortgage [Member] | Home Equity - 2nd Lien [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	558		156
Unpaid Principal Balance, with an allowance for loan losses recorded	573		155
Recorded Investment	558		156
Unpaid Principal Balance	573		155
Related Allowance	122		9
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	357	178
Interest Income Recognized, with an allowance for loan losses recorded	3	2
Average Recorded Investment	357	178
Interest Income Recognized	3	2
Installment [Member] | Home Equity - 1st Lien [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		1
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		122
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	1,387		1,440
Unpaid Principal Balance, with an allowance for loan losses recorded	1,568		1,524
Recorded Investment	1,387		1,441
Unpaid Principal Balance	1,568		1,646
Related Allowance	101		89
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	1	1
Interest Income Recognized, with no related allowance for loan losses recorded	0	2
Average Recorded Investment, with an allowance for loan losses recorded	1,414	1,645
Interest Income Recognized, with an allowance for loan losses recorded	24	29
Average Recorded Investment	1,415	1,646
Interest Income Recognized	24	31
Installment [Member] | Home Equity - 2nd Lien [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	18		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	1,472		1,471
Unpaid Principal Balance, with an allowance for loan losses recorded	1,479		1,491
Recorded Investment	1,472		1,471
Unpaid Principal Balance	1,497		1,491
Related Allowance	107		92
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	1,472	1,777
Interest Income Recognized, with an allowance for loan losses recorded	22	27
Average Recorded Investment	1,472	1,777
Interest Income Recognized	22	27
Installment [Member] | Boat Lending [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	5		5
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	101		0
Unpaid Principal Balance, with an allowance for loan losses recorded	166		0
Recorded Investment	101		0
Unpaid Principal Balance	171		5
Related Allowance	36		0
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	51	1
Interest Income Recognized, with an allowance for loan losses recorded	0	0
Average Recorded Investment	51	1
Interest Income Recognized	0	0
Installment [Member] | Recreational Vehicle Lending [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	0		0
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	82		79
Unpaid Principal Balance, with an allowance for loan losses recorded	90		79
Recorded Investment	82		79
Unpaid Principal Balance	90		79
Related Allowance	7		4
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	81	89
Interest Income Recognized, with an allowance for loan losses recorded	1	1
Average Recorded Investment	81	89
Interest Income Recognized	1	1
Installment [Member] | Other [Member]
Impaired Loans by class [Abstract]
Recorded Investment, with no related allowance for loan losses recorded	0		0
Unpaid Principal Balance, with no related allowance for loan losses recorded	15		15
With no related allowance for loan losses recorded	0		0
Recorded Investment, with an allowance for loan losses recorded	481		379
Unpaid Principal Balance, with an allowance for loan losses recorded	538		406
Recorded Investment	481		379
Unpaid Principal Balance	553		421
Related Allowance	72		$ 21
Average recorded investment in and interest income earned on impaired loans by class [Abstract]
Average Recorded Investment, with no related allowance for loan losses recorded	0	0
Interest Income Recognized, with no related allowance for loan losses recorded	0	0
Average Recorded Investment, with an allowance for loan losses recorded	430	406
Interest Income Recognized, with an allowance for loan losses recorded	6	6
Average Recorded Investment	430	406
Interest Income Recognized	$ 6	$ 6