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Events of default percentage of principal and accrued and unpaid interest due and payable upon default.

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Fair value of the liability component immediately before extinguishment.

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The minimum percentage of the product of the common stock trading price multiplied by the conversion rate during the measurement period as compared to the principal note amount that triggers a conversion option on the notes, if it falls below this percentage.

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Principal amount on conversion rate.

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Trading days during observation period.

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The amount of subsequent adjustments to additional paid in capital for convertible financial instruments where a component of equity and a component of debt are recognized.

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

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Remaining amortization period for discount on the liability component of convertible debt which may be settled in cash upon conversion, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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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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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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Value of input used to measure debt instrument, including, but not limited to, convertible and non-convertible debt.

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Percentage of principal amount of debt redeemed.

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

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Convertible Senior Notes - Additional Information (Details) $ / shares in Units, shares in Millions		1 Months Ended	12 Months Ended
	May 02, 2017 USD ($) d $ / shares shares	Nov. 30, 2020 USD ($)	Dec. 31, 2021 USD ($) d $ / shares	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Principal			$ 381,200,000	$ 381,300,000
Equity component of repurchased convertible senior notes				47,500,000
Loss on extinguishment of convertible senior notes			$ 0	18,400,000	$ 0
2.25% Convertible senior notes due 2024
Debt Instrument [Line Items]
Principal	$ 517,500,000
Proceeds from issuance	$ 502,800,000
Stated interest rate percentage	2.25%
Aggregate principal amount repurchased		$ 136,200,000
Aggregate repurchase price paid in cash		186,900,000
Fair value of the liability component immediately before extinguishment		130,700,000
Equity component of repurchased convertible senior notes		56,300,000
Carrying amount of the liability component at settlement		112,400,000
Loss on extinguishment of convertible senior notes		$ 18,400,000
Threshold percentage of common stock price trigger			130.00%
Common stock price trigger (in USD per share) \| $ / shares			$ 98.70
Threshold common stock trading days \| d			20
Threshold consecutive common stock trading days \| d			30
Principal amount on conversion rate	$ 1,000
Trading days during observation period	30 days
Conversion ratio	0.00131711
Conversion price (in USD per share) \| $ / shares	$ 75.92
Shares issued to settle notes at initial conversion rate (in shares) \| shares	5.0
Conversion premium	42.50%
Market price of common stock (in USD per share) \| $ / shares	$ 53.28
Redemption rate	100.00%
Carrying amount of the liability component upon issuance	$ 368,300,000
Assumed borrowing rate	7.50%
Carrying amount of the equity component upon issuance	$ 149,200,000
Term	7 years
Remaining discount amortization period			2 years 4 months 24 days
Transaction cost related to issuance of convertible senior note	$ 14,700,000
Events of default percentage of principal and accrued and unpaid interest due and payable upon default	100.00%
Fair value			$ 464,700,000	$ 514,300,000
2.25% Convertible senior notes due 2024 \| Conversion Period One
Debt Instrument [Line Items]
Threshold percentage of common stock price trigger	130.00%
Threshold common stock trading days \| d	20
Threshold consecutive common stock trading days \| d	30
2.25% Convertible senior notes due 2024 \| Conversion Period Two
Debt Instrument [Line Items]
Threshold common stock trading days \| d	5
Threshold consecutive common stock trading days \| d	5
Principal amount on conversion rate	$ 1,000
Minimum percentage of common stock price trigger	98.00%
2.25% Convertible senior notes due 2024 \| Discount rate
Debt Instrument [Line Items]
Discount rate		0.0337