Loans (Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 46,859	$ 16,278
Provision for credit loss expense	(1,500)	5,150
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(372)	(569)
Recoveries collected	112	129
Total ending allowance balance	45,099	36,641
Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		8,767
Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		6,886
Commercial and Industrial Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	6,445	4,799
Provision for credit loss expense	(22)	(137)
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(190)	(296)
Recoveries collected	15	12
Total ending allowance balance	6,248	8,814
Commercial and Industrial Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		2,245
Commercial and Industrial Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		2,191
Commercial Real Estate Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	29,878	4,692
Provision for credit loss expense	(1,334)	5,167
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(9)	0
Recoveries collected	5	3
Total ending allowance balance	28,540	17,310
Commercial Real Estate Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		3,063
Commercial Real Estate Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		4,385
Agricultural Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	6,756	5,315
Provision for credit loss expense	(294)	(396)
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	0	0
Recoveries collected	0	0
Total ending allowance balance	6,462	6,485
Agricultural Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		1,438
Agricultural Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		128
Leases
Allowance for Credit Losses [Roll Forward]
Beginning balance	200	0
Provision for credit loss expense	1	67
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	0	0
Recoveries collected	0	0
Total ending allowance balance	201	172
Leases \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		105
Leases \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		0
Consumer Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	490	434
Provision for credit loss expense	(18)	205
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(125)	(237)
Recoveries collected	92	112
Total ending allowance balance	439	455
Consumer Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		(59)
Consumer Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		0
Home Equity Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	996	200
Provision for credit loss expense	(31)	(20)
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	0	0
Recoveries collected	0	0
Total ending allowance balance	965	977
Home Equity Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		762
Home Equity Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		35
Credit Cards
Allowance for Credit Losses [Roll Forward]
Beginning balance	150	0
Provision for credit loss expense	59	35
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(47)	(36)
Recoveries collected	0	1
Total ending allowance balance	162	124
Credit Cards \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		124
Credit Cards \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		0
Residential Mortgage Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance	1,944	333
Provision for credit loss expense	139	229
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	(1)	0
Recoveries collected	0	1
Total ending allowance balance	2,082	2,304
Residential Mortgage Loans \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		1,594
Residential Mortgage Loans \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		147
Unallocated
Allowance for Credit Losses [Roll Forward]
Beginning balance	0	505
Provision for credit loss expense	0	0
Initial allowance on loans purchased with credit deterioration		0
Loans charged-off	0	0
Recoveries collected	0	0
Total ending allowance balance	$ 0	0
Unallocated \| Impact of ASC 326 Adoption \| Non-PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		(505)
Unallocated \| Impact of ASC 326 Adoption \| PCD Loans
Allowance for Credit Losses [Roll Forward]
Beginning balance		$ 0

Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of increase in allowance for credit loss on financing receivable purchased with credit deterioration.

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- Definition

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of increase in allowance for credit loss on financing receivable from recovery.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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