Loans, Loan Portfolio Aging Analysis, Segregated by Class (Details) - USD ($)		3 Months Ended
		Mar. 31, 2020	Dec. 31, 2019
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		$ 57,033,000	$ 55,255,000
Current		3,230,508,000	3,193,409,000
Total Loans		3,287,541,000	3,248,664,000
90+ and Accruing		18,044,000	19,620,000	[1]
30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		13,734,000	10,689,000
60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		11,383,000	13,232,000
90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		31,916,000	31,334,000
Commercial [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		34,901,000
Current		1,642,042,000
Total Loans		1,676,943,000	1,664,948,000
90+ and Accruing		12,376,000
Commercial [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		5,454,000
Commercial [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		6,668,000
Commercial [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		22,779,000
Commercial [Member] | Hotel/Motel [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		133,000
Current		248,584,000
Total Loans		248,717,000
90+ and Accruing		$ 133,000
Percentage of total loan		7.50%
Minimum threshold amount of loans requiring performance bond		$ 500,000
Commercial [Member] | Hotel/Motel [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Commercial [Member] | Hotel/Motel [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Commercial [Member] | Hotel/Motel [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		133,000
Commercial [Member] | Commercial Real Estate Residential [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		9,054,000
Current		253,011,000
Total Loans		262,065,000
90+ and Accruing		4,636,000
Minimum threshold amount of loans requiring performance bond		500,000
Commercial [Member] | Commercial Real Estate Residential [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,514,000
Commercial [Member] | Commercial Real Estate Residential [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,412,000
Commercial [Member] | Commercial Real Estate Residential [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		6,128,000
Commercial [Member] | Commercial Real Estate Nonresidential [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		16,751,000
Current		754,936,000
Total Loans		771,687,000
90+ and Accruing		7,128,000
Minimum threshold amount of loans requiring performance bond		500,000
Commercial [Member] | Commercial Real Estate Nonresidential [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		2,257,000
Commercial [Member] | Commercial Real Estate Nonresidential [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		4,570,000
Commercial [Member] | Commercial Real Estate Nonresidential [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		9,924,000
Commercial [Member] | Dealer Floorplans [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Current		80,828,000
Total Loans		80,828,000
90+ and Accruing		0
Commercial [Member] | Dealer Floorplans [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Commercial [Member] | Dealer Floorplans [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Commercial [Member] | Dealer Floorplans [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		0
Commercial [Member] | Commercial Other [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		8,963,000	7,431,000
Current		304,683,000	382,252,000
Total Loans		313,646,000	389,683,000
90+ and Accruing		479,000	2,586,000	[1]
Commercial [Member] | Commercial Other [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,683,000	880,000
Commercial [Member] | Commercial Other [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		686,000	284,000
Commercial [Member] | Commercial Other [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		6,594,000	6,267,000
Commercial [Member] | Construction [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			585,000
Current			104,224,000
Total Loans			104,809,000
90+ and Accruing	[1]		237,000
Commercial [Member] | Construction [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			118,000
Commercial [Member] | Construction [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			0
Commercial [Member] | Construction [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			467,000
Commercial [Member] | Real Estate Mortgage [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			21,069,000
Current			1,148,906,000
Total Loans			1,169,975,000
90+ and Accruing	[1]		8,820,000
Commercial [Member] | Real Estate Mortgage [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			2,734,000
Commercial [Member] | Real Estate Mortgage [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			5,969,000
Commercial [Member] | Real Estate Mortgage [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			12,366,000
Commercial [Member] | Equipment Lease Financing [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			0
Current			481,000
Total Loans			481,000
90+ and Accruing	[1]		0
Commercial [Member] | Equipment Lease Financing [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			0
Commercial [Member] | Equipment Lease Financing [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			0
Commercial [Member] | Equipment Lease Financing [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			0
Residential [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		15,336,000
Current		895,392,000
Total Loans		910,728,000
90+ and Accruing		5,165,000
Residential [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		3,392,000
Residential [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		3,310,000
Residential [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		8,634,000
Residential [Member] | Construction [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			803,000
Current			62,547,000
Total Loans			63,350,000
90+ and Accruing	[1]		0
Residential [Member] | Construction [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			117,000
Residential [Member] | Construction [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			52,000
Residential [Member] | Construction [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due			634,000
Residential [Member] | Real Estate Mortgage [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		13,616,000	16,470,000
Current		785,275,000	716,533,000
Total Loans		798,891,000	733,003,000
90+ and Accruing		4,730,000	7,088,000	[1]
Residential [Member] | Real Estate Mortgage [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		2,561,000	774,000
Residential [Member] | Real Estate Mortgage [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		3,154,000	5,376,000
Residential [Member] | Real Estate Mortgage [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		7,901,000	10,320,000
Residential [Member] | Home Equity Lines [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,720,000	2,232,000
Current		110,117,000	109,662,000
Total Loans		111,837,000	111,894,000
90+ and Accruing		435,000	344,000	[1]
Residential [Member] | Home Equity Lines [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		831,000	1,084,000
Residential [Member] | Home Equity Lines [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		156,000	412,000
Residential [Member] | Home Equity Lines [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		733,000	736,000
Consumer [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		6,796,000
Current		693,074,000
Total Loans		699,870,000
90+ and Accruing		503,000
Consumer [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		4,888,000
Consumer [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,405,000
Consumer [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		503,000
Consumer [Member] | Consumer Direct [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		1,362,000	1,272,000
Current		144,041,000	146,779,000
Total Loans		145,403,000	148,051,000
90+ and Accruing		38,000	97,000	[1]
Consumer [Member] | Consumer Direct [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		735,000	945,000
Consumer [Member] | Consumer Direct [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		589,000	230,000
Consumer [Member] | Consumer Direct [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		38,000	97,000
Consumer [Member] | Consumer Indirect [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		5,434,000	5,393,000
Current		549,033,000	522,025,000
Total Loans		554,467,000	527,418,000
90+ and Accruing		465,000	448,000	[1]
Consumer [Member] | Consumer Indirect [Member] | 30-59 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		4,153,000	4,037,000
Consumer [Member] | Consumer Indirect [Member] | 60-89 Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		816,000	909,000
Consumer [Member] | Consumer Indirect [Member] | 90+ Days Past Due [Member]
Bank's Loan portfolio aging analysis, segregated by class [Abstract]
Total Past Due		$ 465,000	$ 447,000

[1] 90+ and Accruing are also included in 90+ Days Past Due column.