Allowance for Credit Losses (Accrued Interest) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Receivables [Abstract]
Loans and Leases	$ 82.7	$ 84.5
Debt Securities
Held to Maturity	74.3	82.3
Available for Sale	110.5	119.0
Other Financial Assets	$ 7.8	$ 14.7

Debt Securities, Accrued Interest, After Allowance For Credit Loss [Abstract]

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Debt Securities, Available-For-Sale, Accrued Interest, After Allowance For Credit Loss

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Debt Securities, Held To Maturity, Accrued Interest After Allowance For Credit Loss

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Financing Receivable, Accrued Interest, After Allowance For Credit Loss

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Other Financial Assets, Accrued Interest, After Allowance For Credit Loss

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