Loans (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2022 USD ($) contract	Sep. 30, 2022 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	3	6
RECORDED INVESTMENT	$ 31.8	$ 32.4
UNPAID PRINCIPAL BALANCE	$ 32.7	$ 33.3
COMMERCIAL
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	2	3
RECORDED INVESTMENT	$ 31.7	$ 32.2
UNPAID PRINCIPAL BALANCE	$ 32.6	$ 33.1
COMMERCIAL \| Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	2
RECORDED INVESTMENT	$ 0.1	$ 0.6
UNPAID PRINCIPAL BALANCE	$ 0.1	$ 0.6
COMMERCIAL \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	1
RECORDED INVESTMENT	$ 31.6	$ 31.6
UNPAID PRINCIPAL BALANCE	$ 32.5	$ 32.5
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	3
RECORDED INVESTMENT	$ 0.1	$ 0.2
UNPAID PRINCIPAL BALANCE	$ 0.1	$ 0.2
Personal \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	3
RECORDED INVESTMENT	$ 0.1	$ 0.2
UNPAID PRINCIPAL BALANCE	$ 0.1	$ 0.2

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

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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
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

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- Definition

Amortized cost of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

+ Details

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