Convertible Senior Notes - Additional Information (Details) $ / shares in Units, shares in Thousands	1 Months Ended			12 Months Ended
	Jun. 30, 2020 USD ($) d $ / shares	Jun. 30, 2019 USD ($) d $ / shares	Jan. 31, 2018 USD ($) $ / shares	Jan. 31, 2022 USD ($) $ / shares shares	Jan. 31, 2021 USD ($)	Jan. 31, 2020 USD ($)
Debt Instrument [Line Items]
Net proceeds from issuance of convertible notes				$ 0	$ 1,355,066,000	$ 786,157,000
Multiples of principal amount	$ 1,000
Interest expense				115,700,000	86,500,000	35,900,000
Coupon interest expense				6,200,000	3,800,000	$ 1,500,000
0.375% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 1,380,000,000	1,380,000,000
Net proceeds from issuance of convertible notes	$ 1,162,300,000
Debt instrument, interest rate	0.375%			0.375%
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	$ 296.4544
Debt instrument, fundamental change, repurchase price, equals to principal amount of convertible notes	100.00%
Debt discount	$ 510,300,000
Transaction costs related to convertible notes	$ 24,900,000
Debt conversion, shares issued (in shares) | shares				4,700
Effective interest rate of the liability component, excluding notes conversions options				8.83%
If-converted value in excess of principal amount				$ 62,500,000
Remaining life period				4 years 4 months 24 days
0.375% Convertible Senior Notes Due 2026 | Conversion Notes Holders Conversion Rights, Circumstances 1
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading/business days | d	20
Debt instrument, convertible, threshold consecutive trading days | d	30
Debt instrument, convertible, threshold percentage of sales price of common stock	130.00%
0.375% Convertible Senior Notes Due 2026 | Conversion Notes Holders Conversion Rights, Circumstances 2
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading/business days | d	5
Debt instrument, convertible, threshold consecutive trading days | d	10
Debt instrument, convertible, threshold percentage of sales price of common stock	98.00%
0.375% Convertible Senior Notes Due 2026 | Common Stock
Debt Instrument [Line Items]
Debt instrument, Initial conversion price per share (in dollars per share) | $ / shares				$ 296.45
0.375% Convertible Senior Notes Due 2026 | Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options				$ 192,800,000
Cap price (Dollars per share) | $ / shares				$ 503.415
0.375% Convertible Senior Notes Due 2026 | Minimum
Debt Instrument [Line Items]
Percentage of principal amount shall be declare as due and payable upon certain events of default	25.00%
0.375% Convertible Senior Notes Due 2026 | Private Placement
Debt Instrument [Line Items]
Debt instrument, principal amount	$ 1,380,000,000
0.125% Convertible Senior Notes Due 2025
Debt Instrument [Line Items]
Debt instrument, principal amount				$ 804,990,000	804,999,000
Net proceeds from issuance of convertible notes		$ 667,400,000
Debt instrument, interest rate		0.125%		0.125%
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		$ 159.5965
Debt instrument, fundamental change, repurchase price, equals to principal amount of convertible notes		100.00%
Debt conversion, shares issued (in shares) | shares				5,000
Effective interest rate of the liability component, excluding notes conversions options				7.05%
If-converted value in excess of principal amount					757,900,000
Remaining life period				3 years 4 months 24 days
0.125% Convertible Senior Notes Due 2025 | Conversion Notes Holders Conversion Rights, Circumstances 1
Debt Instrument [Line Items]
Debt instrument, convertible, threshold trading/business days | d		20
Debt instrument, convertible, threshold consecutive trading days | d		30
Debt instrument, convertible, threshold percentage of sales price of common stock		130.00%
0.125% Convertible Senior Notes Due 2025 | Common Stock
Debt Instrument [Line Items]
Debt instrument, Initial conversion price per share (in dollars per share) | $ / shares				$ 159.60
0.125% Convertible Senior Notes Due 2025 | Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options				$ 118,700,000
Cap price (Dollars per share) | $ / shares				$ 295.550
0.125% Convertible Senior Notes Due 2025 | Private Placement
Debt Instrument [Line Items]
Debt instrument, principal amount		$ 805,000,000
0.375% Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Debt instrument, principal amount			$ 230,000,000	$ 1,752,000	8,832,000
Net proceeds from issuance of convertible notes			$ 200,400,000
Debt instrument, interest rate			0.375%	0.375%
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			$ 44.5068
Debt conversion, principal amount				$ 7,100,000
Debt conversion, shares issued (in shares) | shares				39
Debt instrument, fair value				$ 32,300,000
Gain (loss) on conversion and cancellation of debt				$ 400,000
Effective interest rate of the liability component, excluding notes conversions options				7.66%
If-converted value in excess of principal amount				$ 3,500,000	$ 52,700,000
Remaining life period				1 year
0.375% Convertible Senior Notes Due 2023 | Common Stock
Debt Instrument [Line Items]
Debt instrument, Initial conversion price per share (in dollars per share) | $ / shares				$ 44.51
Debt conversion, shares issued (in shares) | shares				132,088,000
0.375% Convertible Senior Notes Due 2023 | Capped Call Options
Debt Instrument [Line Items]
Purchase price of capped call options				$ 23,300,000
Cap price (Dollars per share) | $ / shares				$ 63.821