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Capped call options cap price.

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Cost of purchased capped call options.

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Debt instruments maturity year.

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Description of convertible notes at option of holders.

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Partially terminated capped call options.

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Principal amount per note used in conversion rate.

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Amount of decrease in additional paid in capital (APIC) resulting from direct costs associated with issuing stock. Includes, but is not limited to, legal and accounting fees and direct costs associated with stock issues under a shelf registration.

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Date the debt agreement requires the first payment to be made, in YYYY-MM-DD format.

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Face (par) amount of debt instrument at time of issuance.

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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The average effective interest rate during the reporting period.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Face (par) amount of the original debt instrument that was repurchased.

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- Details

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Convertible Senior Notes - Additional Information (Details)		1 Months Ended			3 Months Ended	6 Months Ended	9 Months Ended	12 Months Ended
	Nov. 01, 2021	Mar. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Nov. 30, 2017 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) $ / shares	Jun. 30, 2018 d	Sep. 30, 2021 USD ($) d $ / shares shares	Dec. 31, 2020 USD ($) shares	Dec. 31, 2019 USD ($) $ / shares
0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Aggregate principal amount		$ 375,000,000.0			$ 375,000,000.0		$ 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%
Debt instrument, fair value							$ 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
Transaction costs attributable to equity component							$ 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							$ 151.04
Debt instrument, maturity year							2026
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			$ 450,000,000.0				$ 450,000,000	$ 450,000,000	$ 450,000,000.0
Debt instrument, interest rate			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%
Debt instrument, fair value							$ 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
Transaction costs attributable to equity component							$ 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							$ 151.04
Interest payment beginning/commencing date			Jun. 15, 2020
Debt instrument, maturity year							2024
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				$ 115,000,000.0			$ 303,000	$ 79,795,000
Debt instrument, interest rate				1.50%			1.50%
Debt instrument, maturity date				Nov. 01, 2022			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						30	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 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%
Debt instrument, fair value							$ 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							$ 151.04
Interest payment beginning/commencing date				May 01, 2018
Modification expense recognized					$ 200,000		$ 200,000
Amended reduce capped call options, cap price \| $ / shares					$ 46.68
Debt instrument, maturity year							2022
1.50% Convertible Senior Notes Due 2022 \| Subsequent Event
Debt Instrument [Line Items]
Debt Instrument, Term	12 months
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							618,462	362,029
Principal amount per note used in conversion rate							$ 20,900,000	$ 12,200,000
Implied interest rate			4.64%						4.64%
Repayments of debt							58,600,000		$ 57,800,000
Repurchase of aggregate principal amount			$ 23,000,000.0				58,600,000		23,000,000.0
Loss on extinguishment of convertible notes					$ 2,200,000		500,000	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							$ 19,500,000	$ 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							4.87%	4.64%
1.50% Convertible Senior Notes Due 2022 Repurchase \| Maximum
Debt Instrument [Line Items]
Implied interest rate							5.13%	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