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Derivatives and Hedging Activities - Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) (Details) - Not Designated as Hedging Instrument - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
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Sep. 30, 2019 | Sep. 30, 2018 | Sep. 30, 2019 | Sep. 30, 2018
Derivative [Line Items] |  |  |  |
Amount of gain recognized in other non-interest income | $ 0.0 | $ 0.1 | $ 0.0 | $ 0.4
Amount of net fee income recognized in other non-interest income | 0.5 | 0.0 | 1.8 | 0.9
Amount of net gains recognized in mortgage banking revenues | $ 0.4 | $ 0.0 | $ 1.5 | $ 0.0

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- Definition Fee Income on Derivatives + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + Details
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- Definition Total amount of gain (loss) derived from fair value hedges recognized in earnings in the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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