Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022 USD ($) contract	Jun. 30, 2021 USD ($) contract	Jun. 30, 2022 USD ($) contract	Jun. 30, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	0	6	3	15
RECORDED INVESTMENT	$ 0.0	$ 7.5	$ 0.6	$ 48.7
UNPAID PRINCIPAL BALANCE	$ 0.0	$ 11.9	$ 0.6	$ 55.1
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	0	1	1	8
RECORDED INVESTMENT	$ 0.0	$ 6.9	$ 0.5	$ 47.9
UNPAID PRINCIPAL BALANCE	$ 0.0	$ 11.2	$ 0.5	$ 54.1
Commercial \| Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	0	0	1	6
RECORDED INVESTMENT	$ 0.0	$ 0.0	$ 0.5	$ 19.6
UNPAID PRINCIPAL BALANCE	$ 0.0	$ 0.0	$ 0.5	$ 19.6
Commercial \| Commercial Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract		1		2
RECORDED INVESTMENT		$ 6.9		$ 28.3
UNPAID PRINCIPAL BALANCE		$ 11.2		$ 34.5
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	0	5	2	7
RECORDED INVESTMENT	$ 0.0	$ 0.6	$ 0.1	$ 0.8
UNPAID PRINCIPAL BALANCE	$ 0.0	$ 0.7	$ 0.1	$ 1.0
Personal \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	0	5	2	7
RECORDED INVESTMENT	$ 0.0	$ 0.6	$ 0.1	$ 0.8
UNPAID PRINCIPAL BALANCE	$ 0.0	$ 0.7	$ 0.1	$ 1.0

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 https://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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