Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) contract	Mar. 31, 2020 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	9	8
RECORDED INVESTMENT	$ 41.2	$ 25.3
UNPAID PRINCIPAL BALANCE	$ 43.2	$ 25.7
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	7	2
RECORDED INVESTMENT	$ 41.0	$ 24.3
UNPAID PRINCIPAL BALANCE	$ 42.9	$ 24.5
Commercial \| Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	6	2
RECORDED INVESTMENT	$ 19.6	$ 24.3
UNPAID PRINCIPAL BALANCE	$ 19.6	$ 24.5
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	6
RECORDED INVESTMENT	$ 0.2	$ 1.0
UNPAID PRINCIPAL BALANCE	$ 0.3	$ 1.2
Personal \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| contract	2	6
RECORDED INVESTMENT	$ 0.2	$ 1.0
UNPAID PRINCIPAL BALANCE	$ 0.3	$ 1.2

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=121611835&loc=SL6953676-111524

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

+ References

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