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Derivatives and Hedging Activities - Schedule of Derivative Instruments, Effect on Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019
Derivative [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax | $ 0.2 | $ 0.0 | $ 0.2 | $ 0.0
Designated as Hedging Instrument [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax | 0.2 | 0.0 | 0.2 | 0.0
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | 0.2 | 0.0 | 0.2 | 0.0
Not Designated as Hedging Instrument |  |  |  |
Derivative [Line Items] |  |  |  |
Amount of net fee income recognized in other non-interest income | 1.7 | 0.5 | 2.7 | 1.3
Amount of net gains recognized in mortgage banking revenues | 0.5 | $ 0.6 | 5.0 | $ 1.0
Cash Flow Hedging [Member] | Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification, Tax | (0.2) |  | (0.2) |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI on Derivatives, before Tax | (0.2) |  | (0.2) |
Cash Flow Hedging [Member] | Interest Rate Floor [Member] | Designated as Hedging Instrument [Member] |  |  |  |
Derivative [Line Items] |  |  |  |
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, before Tax | 0.1 |  | 0.1 |
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net | $ 0.1 |  | $ 0.1 |

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- Definition The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4D -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624177-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + 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=121590274&loc=SL5624171-113959 + Details
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- Definition Amount, before reclassification, of tax expense (benefit) for gain (loss) from derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e640-108580 + Details
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- Definition Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e689-108580 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5624171-113959 + Details
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