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Convertible Senior Notes - Additional Information (Details)	1 Months Ended			3 Months Ended	6 Months Ended	12 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Nov. 30, 2017 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) d $ / shares shares	Jun. 30, 2018 d	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares
0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Aggregate principal amount	$ 375,000,000			$ 375,000,000
Debt instrument, interest rate	0.00%			0.00%
Debt instrument, maturity date	Mar. 15, 2026
Debt instrument, interest rate terms				The Company will pay special interest, if any, at the Company’s election as the sole remedy relating to the failure to comply with certain reporting obligations and under certain circumstances.
Debt Conversion, initial conversion rate \| shares	5.5341
Principal amount per note used in conversion rate	$ 1,000			$ 1,000
Conversion price per share \| $ / shares	$ 180.70			$ 180.70
Shares issuable upon conversion of debt \| shares	2,100,000
Number of trading days \| d				20
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
Description of convertible notes at option of holders				On or after December 15, 2025 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2026 Notes at the conversion rate at any time regardless of whether the conditions set forth above have been met.
Redemption price, percentage				100.00%
Implied interest rate	7.25%			7.25%
Debt instrument, fair value	$ 269,600,000			$ 269,600,000
Difference between aggregate principal amount and estimated fair value of liability component recorded in additional paid-in capital				105,400,000
Transaction costs attributable to liability component	7,600,000			7,600,000
Transaction costs attributable to equity component	3,000,000.0			$ 3,000,000.0
Initial strike price of capped call options \| $ / shares				$ 180.70
Capped call options, cap price \| $ / shares				$ 258.14
Cost of purchased capped call options	$ 35,100,000			$ 35,100,000
Share Price \| $ / shares	$ 121.18			$ 121.18
0% Convertible Senior Notes Due 2026 \| Scenario One
Debt Instrument [Line Items]
Number of trading days \| d				20
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
0% Convertible Senior Notes Due 2026 \| Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days \| d				10
Percentage of last reported sale price to conversion price on each applicable trading day				98.00%
Notes measurement period				5 days
0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Aggregate principal amount	$ 450,000,000	$ 450,000,000.0		$ 450,000,000		$ 450,000,000	$ 450,000,000.0
Debt instrument, interest rate	0.125%	0.125%		0.125%			0.125%
Debt instrument, maturity date		Dec. 15, 2024		Dec. 15, 2024
Debt instrument, interest rate terms				Interest is payable semiannually in arrears on June 15 and December 15 of each year, commencing on June 15, 2020.
Debt Conversion, initial conversion rate \| shares		8.8999
Principal amount per note used in conversion rate		$ 1,000					$ 1,000
Conversion price per share \| $ / shares		$ 112.36					$ 112.36
Shares issuable upon conversion of debt \| shares		4,000,000.0
Number of trading days \| d				20
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
Description of convertible notes at option of holders				On or after June 15, 2024 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2024 Notes at the conversion rate at any time regardless of whether the conditions set forth above have been met.
Redemption price, percentage				100.00%
Implied interest rate	5.16%			5.16%
Debt instrument, fair value	$ 360,400,000			$ 360,400,000
Difference between aggregate principal amount and estimated fair value of liability component recorded in additional paid-in capital				89,600,000
Transaction costs attributable to liability component	10,200,000			10,200,000
Transaction costs attributable to equity component	$ 2,600,000			$ 2,600,000
Initial strike price of capped call options \| $ / shares				$ 112.36
Capped call options, cap price \| $ / shares				$ 166.46
Cost of purchased capped call options		$ 44,900,000		$ 44,900,000
Share Price \| $ / shares	$ 121.18			$ 121.18
Interest payment beginning/commencing date		Jun. 15, 2020
0.125% Convertible Senior Notes Due 2024 \| Scenario One
Debt Instrument [Line Items]
Number of trading days \| d				20
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
0.125% Convertible Senior Notes Due 2024 \| Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days \| d				10
Percentage of last reported sale price to conversion price on each applicable trading day				98.00%
Notes measurement period				5 days
1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 1,538,000		$ 115,000,000.0	$ 1,538,000		$ 79,795,000
Debt instrument, interest rate	1.50%		1.50%	1.50%
Debt instrument, maturity date			Nov. 01, 2022
Debt instrument, interest rate terms				Interest is payable semiannually in arrears on May 1 and November 1 of each year, commencing on May 1, 2018
Debt Conversion, initial conversion rate \| shares			29.6626
Principal amount per note used in conversion rate			$ 1,000
Conversion price per share \| $ / shares			$ 33.71
Shares issuable upon conversion of debt \| shares			3,400,000
Number of trading days \| d				20	30
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
Description of convertible notes at option of holders				On or after May 1, 2022, until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their 2022 Notes at the conversion rate at any time regardless of whether the conditions set forth above have been met.
Redemption price, percentage				100.00%
Implied interest rate	6.93%			6.93%
Debt instrument, fair value	$ 92,100,000			$ 92,100,000
Difference between aggregate principal amount and estimated fair value of liability component recorded in additional paid-in capital				$ 22,900,000
Transaction costs attributable to equity component			$ 800,000
Initial strike price of capped call options \| $ / shares				$ 33.71
Capped call options, cap price \| $ / shares				47.20
Cost of purchased capped call options			$ 12,900,000
Share Price \| $ / shares	$ 121.18			$ 121.18
Interest payment beginning/commencing date			May 01, 2018
Repayments of debt	$ 58,600,000
Repurchase of aggregate principal amount	58,600,000			$ 58,600,000
Partially terminated capped call options	$ 10,600,000
Issuance of common stock \| shares	1,288,994
Modification expense recognized				$ 200,000
Amended reduce capped call options, cap price \| $ / shares				$ 46.68
1.50% Convertible Senior Notes Due 2022 \| Maximum
Debt Instrument [Line Items]
Transaction costs attributable to liability component			$ 100,000
1.50% Convertible Senior Notes Due 2022 \| Scenario One
Debt Instrument [Line Items]
Number of trading days \| d				20
Number of consecutive trading days \| d				30
Percentage of last reported sale price to conversion price on each applicable trading day				130.00%
1.50% Convertible Senior Notes Due 2022 \| Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days \| d				5
Percentage of last reported sale price to conversion price on each applicable trading day				98.00%
Notes measurement period				5 days
1.50% Convertible Senior Notes Due 2022 Repurchase
Debt Instrument [Line Items]
Debt Conversion, initial conversion rate \| shares				581,829		362,029
Principal amount per note used in conversion rate	$ 19,600,000			$ 19,600,000		$ 12,200,000
Implied interest rate	5.13%	4.64%		5.13%			4.64%
Repayments of debt				$ 58,600,000			$ 57,800,000
Repurchase of aggregate principal amount	$ 58,600,000	$ 23,000,000.0		58,600,000			23,000,000.0
Loss on extinguishment of convertible notes	$ 2,200,000			400,000		400,000	1,400,000
Remaining consideration allocated to reacquisition of equity component				2,700,000			36,700,000
Partially terminated capped call options				10,600,000			5,800,000
Additional paid-in capital related to shares issued				$ 18,400,000		$ 11,400,000
Issuance of common stock \| shares				1,288,994
Implied interest rate	4.87%
Modification expense recognized				$ 200,000
1.50% Convertible Senior Notes Due 2022 Repurchase \| Minimum
Debt Instrument [Line Items]
Implied interest rate						4.64%
1.50% Convertible Senior Notes Due 2022 Repurchase \| Maximum
Debt Instrument [Line Items]
Implied interest rate						5.13%
Option to Purchase \| 0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Aggregate principal amount	$ 50,000,000.0			$ 50,000,000.0
Option to Purchase \| 0.125% Convertible Senior Notes Due 2024
Debt Instrument [Line Items]
Aggregate principal amount		$ 75,000,000.0					$ 75,000,000.0
Option to Purchase \| 1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount			$ 15,000,000.0