Loans - TDR Activity by Loan Category (Details) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) loan	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) contract loan payment_deferral	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($) loan
Financing Receivable, Troubled Debt Restructuring [Line Items]
Financing receivable, period of successful payment history used for restructured loan accrual status			6 months
Troubled Debt Restructurings
Number of Contracts \| contract			1
Pre- Modification Outstanding Recorded Investment			$ 179
Post- Modification Outstanding Recorded Investment			$ 179
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
Number of restructured loans \| loan	9		9		13
Total restructured loans	$ 4,571		$ 4,571		$ 5,187
TDR activity by loan category [Roll Forward]
Beginning balance	5,155	$ 6,183	5,187	$ 7,059
Additions	0	0	179	0
Principal (reductions) additions	(584)	(857)	(795)	(1,733)
Charge-offs	0	(30)	0	(30)
Ending balance	4,571	5,296	4,571	5,296
Allowance for loan loss	402	617	402	617
Defaults	0	0	$ 0	0
Number of payment deferral \| payment_deferral			23
Outstanding loans modified due to COVID-19	661,482		$ 661,482
Commercial and Industrial
TDR activity by loan category [Roll Forward]
Beginning balance	0	38	9	75
Additions	0	0	0	0
Principal (reductions) additions	0	(18)	(9)	(55)
Charge-offs	0	0	0	0
Ending balance	0	20	0	20
Allowance for loan loss	0	0	0	0
Defaults	0	0	0	0
Outstanding loans modified due to COVID-19	65,742		$ 65,742
Commercial and Industrial \| Commercial and business loans
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract
Recorded Investment on Defaulted TDRs			$ 0
Commercial and Industrial \| Government program loans
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
Real estate mortgage \| Commercial real estate
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
TDR activity by loan category [Roll Forward]
Beginning balance	889	907	898	1,305
Additions	0	0	0	0
Principal (reductions) additions	(5)	(5)	(14)	(403)
Charge-offs	0	0	0	0
Ending balance	884	902	884	902
Allowance for loan loss	171	346	171	346
Defaults	0	0	$ 0	0
Real estate mortgage \| Residential mortgages
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
TDR activity by loan category [Roll Forward]
Beginning balance	1,037	1,842	1,060	2,029
Additions	0	0	0	0
Principal (reductions) additions	(491)	(771)	(514)	(958)
Charge-offs	0	0	0
Ending balance	546	1,071	546	1,071
Allowance for loan loss	16	15	16	15
Defaults	0	0	$ 0	0
Real estate mortgage \| Home improvement and home equity loans
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
TDR activity by loan category [Roll Forward]
Beginning balance	0	0	0	0
Additions	0	0	0	0
Principal (reductions) additions	0	0	0	0
Charge-offs	0	0	0	0
Ending balance	0	0	0	0
Allowance for loan loss	0	0	0	0
Defaults	0	0	$ 0	0
Real estate construction and development
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
TDR activity by loan category [Roll Forward]
Beginning balance	2,536	2,738	2,654	2,838
Additions	0	0	0	0
Principal (reductions) additions	(50)	(33)	(168)	(133)
Charge-offs	0	0	0	0
Ending balance	2,486	2,705	2,486	2,705
Allowance for loan loss	0	0	0	0
Defaults	0	0	$ 0	0
Agricultural loans
Troubled Debt Restructurings
Number of Contracts \| contract			1
Pre- Modification Outstanding Recorded Investment			$ 179
Post- Modification Outstanding Recorded Investment			$ 179
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
TDR activity by loan category [Roll Forward]
Beginning balance	693	658	566	812
Additions	0	0	179	0
Principal (reductions) additions	(38)	(30)	(90)	(184)
Charge-offs	0	(30)	0	(30)
Ending balance	655	598	655	598
Allowance for loan loss	215	256	215	256
Defaults	0	0	0	0
Outstanding loans modified due to COVID-19	51,587		51,587
Installment and student loans
TDR activity by loan category [Roll Forward]
Beginning balance	0	0	0	0
Additions	0	0	0	0
Principal (reductions) additions	0	0	0	0
Charge-offs	0	0	0	0
Ending balance	0	0	0	0
Allowance for loan loss	0	0	0	0
Defaults	0	$ 0	0	$ 0
Outstanding loans modified due to COVID-19	$ 62,415		$ 62,415
Installment and student loans \| Installment and student loans
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0
Installment and student loans \| Overdraft protection lines
Troubled Debt Restructurings
Number of Contracts \| contract			0
Pre- Modification Outstanding Recorded Investment			$ 0
Post- Modification Outstanding Recorded Investment			$ 0
Number of Contracts which Defaulted During Period \| contract			0
Recorded Investment on Defaulted TDRs			$ 0

Financing Receivable, After Allowance For Credit Loss, Modified

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Allowance for loan losses of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

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No definition available.

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Financing Receivables, Impaired, Troubled Debt Restructuring, Credit Losses Write Offs

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Number Of Payment Deferrals

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Number of financing receivables that have been restructured.

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Amount of investment related to financing receivables restructured by troubled debt restructurings.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, before troubled debt restructuring, of financing receivable to be modified.

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Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

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