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Derivative and Hedging Activities - Schedule of Cumulative Basis Adjustment for Fair Value Hedges (Parenthetical) (Details) - USD ($) $ in Millions | Mar. 31, 2021 | Dec. 31, 2020
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Designated as Hedging Instrument |  |
Derivative [Line Items] |  |
Derivative, notional amount | $ 2,000.0 | $ 2,000.0
Loans and Leases |  |
Derivative [Line Items] |  |
Amortized cost basis | 3,400.0 | 3,600.0
Cumulative basis adjustment associated with hedging relationships | $ 48.0 | $ 73.2

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- Definition Amortized cost of closed portfolio of prepayable financial asset and beneficial interest secured by prepayable financial instrument, used to designate hedging relationship in which hedged item is last layer expected to be remaining at end of hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EEE -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL109999718-113959 + Details
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- Definition Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations. + References No definition available. + Details
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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959 + Details
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