Loans (Allowance for Credit Losses) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Allowance for Credit Losses [Roll Forward]
Beginning balance	$ 39,995	$ 42,431	$ 46,859	$ 16,278
Provision (Benefit) for credit loss expense	(2,000)	4,500	(8,500)	15,550
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	(279)	(322)	(892)	(1,090)
Recoveries collected	82	159	331	377
Total ending allowance balance	37,798	46,768	37,798	46,768
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	6,080	8,787	6,445	4,799
Provision (Benefit) for credit loss expense	1,965	(1,017)	1,747	(1,182)
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	0	(73)	(190)	(369)
Recoveries collected	9	3	52	16
Total ending allowance balance	8,054	7,700	8,054	7,700
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	24,220	22,369	29,878	4,692
Provision (Benefit) for credit loss expense	(2,833)	5,931	(8,502)	16,145
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	0	(9)	(10)	(9)
Recoveries collected	5	91	26	106
Total ending allowance balance	21,392	28,382	21,392	28,382
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	5,847	7,030	6,756	5,315
Provision (Benefit) for credit loss expense	(1,152)	(315)	(2,061)	(166)
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	0	0	0	0
Recoveries collected	0	0	0	0
Total ending allowance balance	4,695	6,715	4,695	6,715
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	204	202	200	0
Provision (Benefit) for credit loss expense	(1)	4	3	101
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	0	0	0	0
Recoveries collected	0	0	0	0
Total ending allowance balance	203	206	203	206
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	460	496	490	434
Provision (Benefit) for credit loss expense	167	70	234	385
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	(204)	(138)	(472)	(520)
Recoveries collected	60	64	231	252
Total ending allowance balance	483	492	483	492
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	908	1,062	996	200
Provision (Benefit) for credit loss expense	124	0	30	65
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	(15)	(67)	(15)	(67)
Recoveries collected	0	0	6	0
Total ending allowance balance	1,017	995	1,017	995
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	181	125	150	0
Provision (Benefit) for credit loss expense	19	39	186	98
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	(16)	(27)	(158)	(86)
Recoveries collected	8	0	14	1
Total ending allowance balance	192	137	192	137
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	2,095	2,360	1,944	333
Provision (Benefit) for credit loss expense	(289)	(212)	(137)	104
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	(44)	(8)	(47)	(39)
Recoveries collected	0	1	2	2
Total ending allowance balance	1,762	2,141	1,762	2,141
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	0	0	505
Provision (Benefit) for credit loss expense	0	0	0	0
Initial allowance on loans purchased with credit deterioration				0
Loans charged-off	0	0	0	0
Recoveries collected	0	0	0	0
Total ending allowance balance	$ 0	$ 0	$ 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 excluding accrued interest, of allowance for credit loss on financing receivable.

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

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

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

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