Loans and Leases (Troubled Debt Restructurings) (Details) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($) Contract	Mar. 31, 2019 USD ($) Contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract	8
RECORDED INVESTMENT	$ 25.3
UNPAID PRINCIPAL BALANCE	$ 25.7
Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract		14
RECORDED INVESTMENT		$ 17.4
UNPAID PRINCIPAL BALANCE		$ 18.7
Commercial
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract	2	1
RECORDED INVESTMENT	$ 24.3	$ 7.6
UNPAID PRINCIPAL BALANCE	$ 24.5	$ 8.8
Commercial \| Commercial and Institutional
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract	2	1
RECORDED INVESTMENT	$ 24.3	$ 7.6
UNPAID PRINCIPAL BALANCE	$ 24.5	$ 8.8
Personal
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract	6	13
RECORDED INVESTMENT	$ 1.0	$ 9.8
UNPAID PRINCIPAL BALANCE	$ 1.2	$ 9.9
Personal \| Residential Real Estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
NUMBER OF LOANS AND LEASES \| Contract	6	13
RECORDED INVESTMENT	$ 1.0	$ 9.8
UNPAID PRINCIPAL BALANCE	$ 1.2	$ 9.9

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=118936363&loc=SL6953676-111524

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

+ References

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