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Debt - Conversion Value of Convertible Notes (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Dec. 31, 2020
Senior Notes | Senior Convertible Notes due 2023 |  |
Debt Instrument [Line Items] |  |
Total by which the notes’ if-converted value exceeds their principal amount | $ 1,024.2 | $ 1,077.5

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- Definition The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031898-161870 + Details
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Balance Type: | credit
Period Type: | duration

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Balance Type: | na
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- Details
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Period Type: |

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- Details
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Namespace Prefix: |
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