Fair Value Disclosure - Significant Unobservable Inputs Used in the Fair Value Measurements (Details) - Level 3 - Fair Value, Nonrecurring $ in Thousands	Sep. 30, 2020 USD ($) $ / ft²	Dec. 31, 2019 USD ($)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans	$ 8,171	$ 3,140
Premises and equipment, net	240	0
Mortgage Servicing Rights	694	930
Other real estate	$ 34	$ 58
Market Comparable Properties \| Marketability Discount \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans, measurement input	0.10
Other real estate owned, measurement input	0.10
Market Comparable Properties \| Marketability Discount \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Impaired loans, measurement input	0.30
Other real estate owned, measurement input	0.30
Market Comparable Properties \| Price Per Square Footage \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Premises and equipment, measurement input (in dollars per share) \| $ / ft²	26.88
Market Comparable Properties \| Price Per Square Footage \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Premises and equipment, measurement input (in dollars per share) \| $ / ft²	34.79
Discounted Cash Flow \| Discount Rate \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage Servicing Rights, measurement input	0.09
Discounted Cash Flow \| Discount Rate \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage Servicing Rights, measurement input	0.11
Discounted Cash Flow \| Prepayment Rate \| Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage Servicing Rights, measurement input	0.157
Discounted Cash Flow \| Prepayment Rate \| Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Mortgage Servicing Rights, measurement input	0.214

The fair value portion of impaired loans.

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Value of input used to measure impaired loans.

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Property, Plant And Equipment, Measurement Input

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Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10(4))
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Value of input used to measure real estate owned by financial institution by financial institution which is not directly related to its business.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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Fair value portion of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 45
-Paragraph 2
-Subparagraph (b)
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Value of input used to measure servicing asset.

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