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Derivative Financial Instruments - Effect on Statement of Comprehensive Income and Statement of Income (Details) - Designated as Hedging Instrument - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Derivative [Line Items] |  |  |  |
Gain (Loss) Recognized in Other Comprehensive Income | $ (1.9) | $ 0.3 | $ (0.9) | $ 13.8
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings | 0.4 | 0.1 | 1.4 | 0.4
Gain (Loss) Recognized in Earnings from Excluded Components | 0.0 | 0.0 | 0.0 | 2.8
Forward foreign currency contracts | Net Investment Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Gain (Loss) Recognized in Other Comprehensive Income | (2.0) | 0.4 | (1.6) | 64.9
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings | 0.4 | 0.1 | 1.4 | 0.4
Gain (Loss) Recognized in Earnings from Excluded Components | 0.0 | 0.0 | 0.0 | 2.8
Put options | Net Investment Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  |  | 0.0 | (47.7)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  |  | 0.0 | 0.0
Gain (Loss) Recognized in Earnings from Excluded Components |  |  | 0.0 | 0.0
Call options | Net Investment Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Gain (Loss) Recognized in Other Comprehensive Income |  |  | 0.0 | (1.3)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings |  |  | 0.0 | 0.0
Gain (Loss) Recognized in Earnings from Excluded Components |  |  | 0.0 | 0.0
Interest rate swap | Cash Flow Hedging |  |  |  |
Derivative [Line Items] |  |  |  |
Gain (Loss) Recognized in Other Comprehensive Income | 0.1 | (0.1) | 0.7 | (2.1)
Gain Reclassified from Accumulated Other Comprehensive Loss into Earnings | 0.0 | 0.0 | 0.0 | 0.0
Gain (Loss) Recognized in Earnings from Excluded Components | $ 0.0 | $ 0.0 | $ 0.0 | $ 0.0

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- Definition Other Comprehensive Income (Loss), Net Investment And Cash Flow Hedge, Gain (Loss), Before Reclassification And Tax + References No definition available. + Details
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- Definition Other Comprehensive Income (Loss), Net Investment And Cash Flow Hedge, Gain (Loss), Reclassification, before Tax + References No definition available. + Details
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- Definition Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying 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 815 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=121577181&loc=SL110061190-113977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5618551-113959 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 Reference 4: 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=124509347&loc=d3e637-108580 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580 + 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=124509347&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=124509347&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=125515794&loc=SL5624171-113959 + Details
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- Definition Amount, before tax and after adjustments, of gain (loss) from increase (decrease) in value of excluded component of derivative designated and qualifying as hedge. Adjustments include, but are not limited to, reclassifications for sale and settlement, and amounts recognized under systematic and rational method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (dd) -URI http://asc.fasb.org/extlink&oid=124509347&loc=SL7669646-108580 + Details
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- Definition Amount, before tax and reclassification, of gain (loss) from derivative designated and qualifying as net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CCC -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109998896-113959 + Details
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- Definition Amount, before tax, of reclassification from accumulated other comprehensive income (AOCI) for gain (loss) from derivative designated and qualifying as net investment hedge. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4CCC -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=125515794&loc=SL109998896-113959 + Details
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