Convertible Senior Notes - Additional Information (Details) - USD ($) $ in Thousands		3 Months Ended
Aug. 13, 2019	Mar. 31, 2020
Debt Instrument [Line Items]
Interest expense related to amortization of debt discount and issuance costs		$ 5,532
0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Proceeds form issuance of convertible note	$ 500,000
Convertible senior notes interest rate	0.125%
Option to purchase aggregate principal amount	$ 65,000
Interest expense related to amortization of debt discount and issuance costs		5,500
Coupon interest expense		$ 200
Remaining life of notes		52 months
0.125% Convertible Senior Notes Due 2024 \| Level 2
Debt Instrument [Line Items]
Estimated fair value of convertible senior notes		$ 491,200

Coupon interest expense.

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- Definition

Debt instrument face amount optional.

+ References

No definition available.

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- Definition

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-SubTopic 30
-Section 45
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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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