Recent Accounting Pronouncements (Impact of ASC 326 in Loan Portfolio Segments as January 1, 2020) (Details) - USD ($) $ in Thousands	Jan. 01, 2020	Jun. 30, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201613Member
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans		$ 3,270,934	$ 3,081,973
Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			0
Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			3,081,973
Commercial and Industrial Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	$ 534,692	795,688	589,758
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 and Industrial Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			532,501
Commercial Real Estate Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	1,500,247	1,473,234	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
Commercial Real Estate Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			1,495,862
Agricultural Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	384,654	373,483	384,526
Agricultural Loans | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	128
Agricultural Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			384,526
Leases
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	57,257	56,728
Leases | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	0		57,257
Leases | Adjusted Balance
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	225,790	216,366	225,755
Home Equity Loans | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	35
Home Equity Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			225,755
Consumer Loans
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	69,264	64,972	81,217
Consumer Loans | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	0		(11,953)
Consumer Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			69,264
Credit Cards
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	11,953	10,217
Credit Cards | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	0		11,953
Credit Cards | Adjusted Balance
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	305,002	$ 280,246	304,855
Residential Mortgage Loans | Impact of ASC 326 Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans	$ 147
Residential Mortgage Loans | Adjusted Balance
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Loans			$ 304,855