Convertible Senior Notes - Additional Information (Details)	1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2020 USD ($) d $ / shares	Jun. 30, 2019 USD ($) d $ / shares	Jan. 31, 2018 USD ($) d $ / shares	Oct. 31, 2022 USD ($) $ / shares	Oct. 31, 2021 USD ($)	Oct. 31, 2022 USD ($) $ / shares shares	Oct. 31, 2021 USD ($)	Jan. 31, 2022 USD ($)
Debt Instrument [Line Items]
Repayments of convertible debt						$ 1,750,000	$ 5,748,000
Interest expense				$ 1,800,000	$ 29,500,000	5,400,000	85,700,000
Coupon interest expense				1,500,000	$ 1,500,000	4,600,000	$ 4,600,000
0.375% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 1,380,000,000		$ 1,380,000,000		$ 1,380,000,000
Net proceeds from issuance of convertible notes	$ 1,162,300,000
Debt instrument, initial conversion rate of shares of common stock per $1,000 principal	0.0033732
Debt instrument, initial conversion price per share (in dollars per share) \| $ / shares	$ 296.45
Debt instrument, interest rate				0.375%		0.375%
Debt instrument, fundamental change, repurchase price, equals to principal amount of convertible notes	100.00%
Effective interest rate of the liability component, excluding notes conversions options				0.68%		0.68%		8.83%
Remaining life period						3 years 7 months 6 days
0.375% Convertible Senior Notes Due 2026 \| Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options						$ 192,800,000
Capped call exercise price (in dollars per share) \| $ / shares				503.415		503.415
0.375% Convertible Senior Notes Due 2026 \| Conversion Notes Holders Conversion Rights, Circumstances 1
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of sales price of common stock	130.00%
Debt instrument, convertible, threshold trading/business days \| d	20
Debt instrument, convertible, threshold consecutive trading days \| d	30
0.375% Convertible Senior Notes Due 2026 \| Private placement
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 1,380,000,000
Debt instrument, interest rate	0.375%
0.125% Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Debt instrument, principal amount		$ 805,000,000.0		$ 804,990,000		$ 804,990,000		$ 804,990,000
Net proceeds from issuance of convertible notes		$ 667,400,000
Debt instrument, initial conversion rate of shares of common stock per $1,000 principal		0.0062658
Debt instrument, initial conversion price per share (in dollars per share) \| $ / shares		$ 159.60
Debt instrument, interest rate		0.125%		0.125%		0.125%
Debt instrument, fundamental change, repurchase price, equals to principal amount of convertible notes		100.00%
Effective interest rate of the liability component, excluding notes conversions options				0.52%		0.52%		7.05%
Remaining life period						2 years 7 months 6 days
0.125% Convertible Senior Notes Due 2025 \| Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options						$ 118,700,000
Capped call exercise price (in dollars per share) \| $ / shares				295.550		295.550
0.125% Convertible Senior Notes Due 2025 \| Conversion Notes Holders Conversion Rights, Circumstances 1
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of sales price of common stock		130.00%
Debt instrument, convertible, threshold trading/business days \| d		20
Debt instrument, convertible, threshold consecutive trading days \| d		30
0.125% Convertible Senior Notes Due 2025 \| Private placement
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 805,000,000.0		$ 805,000,000.0
0.375% Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Debt instrument, principal amount			$ 230,000,000.0	$ 2,000		$ 2,000		$ 1,752,000
Net proceeds from issuance of convertible notes			$ 200,400,000
Debt instrument, initial conversion rate of shares of common stock per $1,000 principal			0.0224685
Debt instrument, initial conversion price per share (in dollars per share) \| $ / shares			$ 44.51
Debt instrument, interest rate			0.375%	0.375%		0.375%
Original debt, amount						$ 1,800,000
Repayments of convertible debt						$ 1,800,000
Debt conversion, shares issued (in shares) \| shares						13,071
Debt conversion, principal amount						$ 800,000
Debt instrument, fundamental change, repurchase price, equals to principal amount of convertible notes			100.00%
If-converted value in excess of principal amount						$ 0		$ 3,500,000
Effective interest rate of the liability component, excluding notes conversions options				1.00%		1.00%		7.66%
Remaining life period						2 months 12 days
0.375% Convertible Senior Notes Due 2023 \| Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options						$ 23,300,000
Capped call exercise price (in dollars per share) \| $ / shares				63.821		63.821
0.375% Convertible Senior Notes Due 2023 \| Conversion Notes Holders Conversion Rights, Circumstances 1
Debt Instrument [Line Items]
Debt instrument, convertible, threshold percentage of sales price of common stock			130.00%
Debt instrument, convertible, threshold trading/business days \| d			20
Debt instrument, convertible, threshold consecutive trading days \| d			30
0.375% Convertible Senior Notes Due 2023 \| Private placement
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 0		$ 0

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