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Convertible Senior Notes - Additional Information (Detail)	1 Months Ended		3 Months Ended
	Jun. 30, 2020 USD ($) $ / shares shares	May 31, 2017 USD ($) $ / shares	Mar. 31, 2021 USD ($) d $ / shares shares	Mar. 31, 2020 d	Apr. 30, 2021 USD ($)
Debt Instrument [Line Items]
Loss on early extinguishment of debt			$ (2,406,000)
0.375% Convertible Senior Notes Due 2025 [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate, stated percentage	0.375%
Debt instrument, maturity date			Jun. 01, 2025
Principal amount of each convertible note	$ 1,000,000,000
Debt instrument, conversion ratio	3.5396
Common stock conversion price \| $ / shares	$ 282.52		$ 282.52
Principal amount settlement, Description			The Company expects to settle the principal amount of the 2025 Notes in cash.
Debt instrument, convertible, threshold trading days \| d			20
Debt instrument, convertible, threshold consecutive trading days \| d			30
Debt instrument, conversion price per share \| $ / shares	$ 282.52		$ 282.52
0.375% Convertible Senior Notes Due 2025 [Member] \| Capped Call Options [Member]
Debt Instrument [Line Items]
Cost of purchased capped call options	$ 50,600,000
Derivative, price risk option strike price \| $ / shares	282.52
Derivative, cap price \| $ / shares	426.44
0.375% Convertible Senior Notes Due 2025 [Member] \| Private Offering [Member]
Debt Instrument [Line Items]
Principal amount of long term debt	$ 400,000,000
0.375% Convertible Senior Notes Due 2025 [Member] \| Over-Allotment Options [Member]
Debt Instrument [Line Items]
Principal amount of long term debt	$ 60,000,000
0.375% Convertible Senior Notes Due 2025 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Percentage of closing price to trigger debt conversion			130.00%
0.375% Convertible Senior Notes Due 2025 [Member] \| Maximum [Member] \| Capped Call Options [Member]
Debt Instrument [Line Items]
Common stock shares covered under capped call transactions \| shares	1,600,000
0.25% Convertible Senior Notes Due 2022 [Member]
Debt Instrument [Line Items]
Principal amount of long term debt		$ 1,000,000,000	$ 81,400,000
Debt instrument, interest rate, stated percentage		0.25%
Debt instrument, maturity date			Jun. 01, 2022
Debt instrument, conversion ratio		10.5519
Common stock conversion price \| $ / shares		$ 94.77
Principal amount settlement, Description			The Company expects to settle the principal amount of the 2022 Notes in cash.
Debt instrument, convertible, threshold trading days \| d				20
Debt instrument, convertible, threshold consecutive trading days \| d				30
Debt instrument, conversion price per share \| $ / shares		$ 94.77
Debt instrument convertible, principal amount			$ 44,500,000
Loss on early extinguishment of debt			2,400,000
Long-term debt, current			$ 11,800,000
Number of common shares to be repurchased under convertible note hedge transactions with certain counterparties \| shares			4,200,000
Hedging option strike price per common stock \| $ / shares			$ 94.77
Warrants expected to settle, description			The Warrants are expected to settle three business days from each trading day commencing on September 1, 2022 and ending on the 79th trading day thereafter.
Settlement period of warrants excess price over strike price			3 days
Warrants expected to settle, commencement date			Sep. 01, 2022
0.25% Convertible Senior Notes Due 2022 [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Warrants holders option to purchase number of shares of company’s common stock \| shares			4,200,000
Warrants exercise price per share \| $ / shares			$ 115.8
Debt instrument cash consideration for conversion			$ 44,500,000
Debt instrument convertible to common stock for cash consideration \| shares			400,000
Debt instrument convertible to common stock \| shares			1,000,000.0
0.25% Convertible Senior Notes Due 2022 [Member] \| Warrants [Member]
Debt Instrument [Line Items]
Debt instrument convertible to common stock \| shares			1,300,000
0.25% Convertible Senior Notes Due 2022 [Member] \| Subsequent Event [Member]
Debt Instrument [Line Items]
Debt instrument convertible, principal amount					$ 12,700,000
0.25% Convertible Senior Notes Due 2022 [Member] \| Private Offering [Member]
Debt Instrument [Line Items]
Principal amount of long term debt		$ 350,000,000
0.25% Convertible Senior Notes Due 2022 [Member] \| Over-Allotment Options [Member]
Debt Instrument [Line Items]
Principal amount of long term debt		$ 50,000,000
0.25% Convertible Senior Notes Due 2022 [Member] \| Maximum [Member]
Debt Instrument [Line Items]
Percentage of closing price to trigger debt conversion				130.00%