Nature of Business and Basis of Presentation - Loan Deferral (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 USD ($) contract loan	Dec. 31, 2020 USD ($) loan contract
Financing Receivable, Modifications [Line Items]
Decrease in deferred loans, percent		86.90%
Total Loans Outstanding	$ 1,642.7
Number of Contracts \| contract	5	5
Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 4.0	$ 30.5
Number of Contracts \| loan	4	43
Accommodation & Food Services
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 94.5
Accommodation & Food Services \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 2.4	$ 14.7
Number of Contracts \| loan	1	16
Real Estate and Rental Leasing
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 560.2
Real Estate and Rental Leasing \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 1.3	$ 5.5
Number of Contracts \| loan	2	10
Other Services Including Private Households
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 173.2
Other Services Including Private Households \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.3	$ 1.1
Number of Contracts \| loan	1	3
Educational Services
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 15.1
Educational Services \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.0
Number of Contracts \| loan	0	0
Construction
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 263.1
Construction \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.0
Number of Contracts \| loan	0	0
Professional, Scientific, and Technical Services
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 43.4
Professional, Scientific, and Technical Services \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 1.4
Number of Contracts \| loan	0	3
Arts, Entertainment & Recreation
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 32.7
Arts, Entertainment & Recreation \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.7
Number of Contracts \| loan	0	2
Retail Trade
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 19.6
Retail Trade \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.3
Number of Contracts \| loan	0	1
Healthcare & Social Assistance
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 79.1
Healthcare & Social Assistance \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.9
Number of Contracts \| loan	0	1
Wholesale Trade
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 21.6
Wholesale Trade \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 0.0
Number of Contracts \| loan	0	0
All other
Financing Receivable, Modifications [Line Items]
Total Loans Outstanding	$ 340.2
All other \| Loan Deferral Due To COVID-19 \| Payment Deferral
Financing Receivable, Modifications [Line Items]
Deferred Loans Balance	$ 0.0	$ 5.9
Number of Contracts \| loan	0	7

Financing Receivable, Modification, Deferred Loans

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- Definition

Financing Receivable, Modification, Deferred Loans, Increase (Decrease), Percent

+ References

No definition available.

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- Definition

Financing Receivable, Small Business Administration, Paycheck Protection Program, After Allowance For Credit Loss

+ References

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- Definition

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.

+ References

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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