Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) contract	Mar. 31, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	3	9
RECORDED INVESTMENT	$ 0.6	$ 41.2
UNPAID PRINCIPAL BALANCE	$ 0.6	43.2
Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
RECORDED INVESTMENT		5.5
UNPAID PRINCIPAL BALANCE		$ 5.5
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	7
RECORDED INVESTMENT	$ 0.5	$ 41.0
UNPAID PRINCIPAL BALANCE	$ 0.5	$ 42.9
Commercial \| Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	1	6
RECORDED INVESTMENT	$ 0.5	$ 19.6
UNPAID PRINCIPAL BALANCE	$ 0.5	$ 19.6
Commercial \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract		1
RECORDED INVESTMENT		$ 21.4
UNPAID PRINCIPAL BALANCE		$ 23.3
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	2	2
RECORDED INVESTMENT	$ 0.1	$ 0.2
UNPAID PRINCIPAL BALANCE	$ 0.1	$ 0.3
Personal \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	2	2
RECORDED INVESTMENT	$ 0.1	$ 0.2
UNPAID PRINCIPAL BALANCE	$ 0.1	$ 0.3

Financing Receivable, Troubled Debt Restructuring, Postmodification, Unpaid Principal Balance

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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

No definition available.

+ Details

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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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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

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