The amount by which the convertible debt's if-converted value exceeds its principle amount at the balance sheet date, regardless of whether the instrument is currently convertible. This element applies to public companies only.

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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.

+ References

No definition available.

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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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No definition available.

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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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No definition available.

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- Definition

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

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- Definition

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

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- Definition

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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- Definition

Gross amount of debt extinguished.

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- Definition

Amount of long-term debt and lease obligation, classified as current.

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- Definition

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

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Long-term Debt - 2.25% Convertible Senior Notes (Details)	9 Months Ended
	Sep. 30, 2021 USD ($) trading_day $ / shares	Dec. 31, 2020 USD ($)	Dec. 14, 2016 USD ($)
Debt Instrument [Line Items]
Current portion of long-term debt	$ 163,600,000	$ 299,900,000
Share price (in USD per share) \| $ / shares	$ 43.55
2 1/4% Notes
Debt Instrument [Line Items]
Extinguishment of debt	$ 154,100,000
2¼% Notes
Debt Instrument [Line Items]
Debt instrument interest rate stated percentage		2.25%
Convertible Debt \| 2 1/4% Notes
Debt Instrument [Line Items]
Debt Instrument, Face Amount			$ 300,000,000
Extinguishment of debt	$ 154,100,000
Debt instrument interest rate stated percentage	2.25%
Debt convertible trigger stock price (in USD per share) \| $ / shares	$ 33.80
Debt convertible threshold trading days \| trading_day	20
Debt convertible threshold consecutive trading days \| trading_day	30
Current portion of long-term debt	$ 135,400,000
Convertible debt threshold percentage of stock price trigger	130.00%
Debt Component of Convertible Debt \| 2 1/4% Notes
Debt Instrument [Line Items]
If-converted value in excess of principal	$ 98,500,000