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Derivative Instruments Cash Flow Hedges (Details) - Foreign Exchange Contract - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Cash flows, revenue | Revenue |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in operating income for the settlement of certain effective cash flow hedge instruments | $ 118.6 | $ (42.5) | $ (32.5)
Net gains (losses) in net income of foreign currency forward contracts, excluded component | 2.9 | 10.8 |
Cash flows, revenue | Other income (expense) |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in net income of foreign currency forward contracts, excluded component |  |  | 8.9
Cash flows, operating expenses | Other income (expense) |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in net income of foreign currency forward contracts, excluded component |  |  | (0.2)
Cash flows, operating expenses | Operating Expense |  |  |
Summary of the effect of derivatives designated as hedging instruments on the consolidated statements of income |  |  |
Net gains (losses) in operating income for the settlement of certain effective cash flow hedge instruments | (3.3) | 0.2 | $ 0.6
Net gains (losses) in net income of foreign currency forward contracts, excluded component | $ 0.2 | $ (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=109980867&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=109980867&loc=SL5624171-113959 + Details
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- Definition The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness. + 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 (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 25 -Section 50 -Paragraph 1 -Subparagraph (a)(1),(2) -URI http://asc.fasb.org/extlink&oid=109977999&loc=d3e76258-113986 + Details
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