It represents the rate of premium based on the last reported sales price of stock.

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Convertible debt conversion rate.

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The cap rate on a debt . A payment or receipt is triggered if the market rate exceeds the cap rate on the debt.

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Amount of payment which is made for entering into privately negotiated capped call transactions.

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

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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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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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Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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The cash inflow from the issuance of long-term debt that is not secured by collateral. Excludes proceeds from tax exempt unsecured debt.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Long-Term Debt - Additional Information (Details)			3 Months Ended		12 Months Ended
Long-Term Debt - Additional Information (Details)	Mar. 31, 2017 shares	Mar. 16, 2016 USD ($)	Mar. 31, 2017 USD ($) $ / shares	Mar. 31, 2016 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 25, 2016 $ / shares
Debt Instrument [Line Items]
Reverse stock split conversion ratio					0.05
Aggregate principal amount of notes issued					$ 325,000,000	$ 325,000,000
Coupon interest rate				3.75%
Sale of stock (in usd per share) \| $ / shares							$ 111.20
Debt issuance costs				$ 10,000,000
Debt instrument, term				7 years
Call Option
Debt Instrument [Line Items]
Conversion premium percentage							75.00%
Payment for capped call transactions				$ 38,500,000
Debt cap price (in usd per share) \| $ / shares							194.60
Debt issuance costs				900,000
Unsecured Debt
Debt Instrument [Line Items]
Convertible debt conversion rate \| $ / shares			0.073411
Aggregate principal amount of notes issued				$ 325,000,000
Net proceeds received		$ 315,000,000
Number of shares issued for debt converted (in shares) \| shares	2,385,800
Debt instrument, convertible, conversion price (in usd per share) \| $ / shares							$ 136.20
Conversion premium percentage							22.50%
Unsecured Debt \| Maximum
Debt Instrument [Line Items]
Convertible debt conversion rate			0.089928