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- Definition

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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Notes measurement period.

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Principal amount per note used in conversion rate.

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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The price per share of the conversion feature embedded in the debt instrument.

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- Definition

Price of the entity's common stock which would be required to be attained for the conversion feature embedded in the debt instrument to become effective.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

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- Definition

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

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- Definition

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

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- Definition

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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Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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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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Price of a single share of a number of saleable stocks of a company.

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Convertible Senior Notes - Additional Information (Details)	1 Months Ended			3 Months Ended		6 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Nov. 30, 2017 USD ($)	Mar. 31, 2022 USD ($) d $ / shares	Mar. 31, 2021 USD ($) $ / shares	Jun. 30, 2018 d	Dec. 31, 2021 USD ($)
0% Convertible Senior Notes Due 2026
Debt Instrument [Line Items]
Aggregate principal amount \| $	$ 375,000,000.0			$ 375,000,000	$ 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%
Effective interest rates	7.30%			0.60%	7.30%
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				$ 43.64
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
Debt instrument, interest rate		0.125%
Debt instrument, maturity date		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
Conversion price per share \| $ / shares		$ 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%
Effective interest rates	5.20%			0.70%	5.20%
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				$ 43.64
Interest payment 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	$ 8,000			$ 8,000
Debt instrument, interest rate			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
Number of trading days \| d						30
Effective interest rates	6.90%			2.20%	6.90%
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				$ 43.64
Interest payment 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
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
Option to Purchase \| 1.50% Convertible Senior Notes Due 2022
Debt Instrument [Line Items]
Aggregate principal amount \| $			$ 15,000,000.0