Carrying Value of Convertible Senior Notes (Parenthetical) (Detail)		12 Months Ended
Jul. 19, 2019	Dec. 31, 2019
0.375% Convertible Senior Notes due 2024
Debt Instrument [Line Items]
Notes, interest rate		0.375%
Notes, due date		Jul. 15, 2024
2.125% Convertible Senior Notes due 2021
Debt Instrument [Line Items]
Notes, interest rate		2.125%
Notes, due date	Jun. 01, 2021	Jun. 01, 2021

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

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- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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