Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail)	9 Months Ended
Sep. 30, 2020	Mar. 31, 2020
Significant Accounting Policies [Line Items]
Amortization period of deferred issuance costs	5 years
Senior Notes \| Convertible Notes
Significant Accounting Policies [Line Items]
Debt instrument stated rate	2.625%	2.625%

Extended 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.

No definition available.

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- Definition

Period when adjustments to the carrying value of an interest-bearing hedged item are amortized upon discontinuation of the interest rate fair value hedge, 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
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 35
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=121561968&loc=d3e75592-113984

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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