Convertible Senior Notes - Schedule of Components of Convertible Senior Notes (Parenthetical) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Transaction costs in equity	$ 2.6
Tax of equity component	0.9
1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Transaction costs in equity	0.8	$ 0.8
Debt instrument, market premium excess of fair value	36.7
Principal balance outstanding	$ 23.0

Debt instrument convertible, tax portion of equity component.

No definition available.

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- Definition

Transaction costs in equity.

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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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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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

+ References

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