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Recent Accounting Pronouncements (Impact of ASC 326 in Balance Sheet as January 1, 2020) (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Jan. 01, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	$ 3,018,416		$ 3,081,973
Allowance for Credit Losses	(36,641)	$ (31,931)	(16,278)	$ (16,243)	$ (15,823)
Allowance for Credit Losses on Unfunded Loan Commitments		(173)
Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			3,081,973
Allowance for Credit Losses			(16,278)
Allowance for Credit Losses on Unfunded Loan Commitments			0
Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Allowance for Credit Losses		(15,653)
Allowance for Credit Losses on Unfunded Loan Commitments		(173)
Commercial and Industrial Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	509,947	534,692	589,758
Allowance for Credit Losses	(8,814)		(4,799)
Commercial and Industrial Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			532,501
Commercial and Industrial Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		2,191	(57,257)
Commercial Real Estate Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	1,489,353	1,500,247	1,495,862
Allowance for Credit Losses	(17,310)		(4,692)	(5,741)	(5,291)
Commercial Real Estate Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			1,495,862
Commercial Real Estate Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		4,385
Agricultural Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	366,286	384,654	384,526
Allowance for Credit Losses	(6,485)		(5,315)	(5,453)	(5,776)
Agricultural Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			384,526
Agricultural Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		128
Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	55,833	57,257
Allowance for Credit Losses	(172)		0
Leases \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			57,257
Leases \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			57,257
Home Equity Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	224,306	225,790	225,755
Allowance for Credit Losses	(977)		(200)	(214)	(229)
Home Equity Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			225,755
Home Equity Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		35
Consumer Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	68,085	69,264	81,217
Allowance for Credit Losses	(455)		(434)	(483)	(420)
Consumer Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			69,264
Consumer Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			(11,953)
Credit Cards
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	11,056	11,953
Allowance for Credit Losses	(124)		0
Credit Cards \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			11,953
Credit Cards \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			11,953
Residential Mortgage Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	293,550	305,002	304,855
Allowance for Credit Losses	$ (2,304)		(333)	$ (429)	$ (472)
Residential Mortgage Loans \| Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			$ 304,855
Residential Mortgage Loans \| Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		$ 147