Aggregate cost for capped call transactions in connection with issuance of convertible debt instruments.

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Cap price stated in the contract for options indexed to the issuer's equity shares.

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Amount of the cost of borrowed funds accounted for as coupon interest expense.

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- Definition

The increase in ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount under certain corporate activity .

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- Definition

The number of shares that the holder of the call would receive if converted to equity.

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No definition available.

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- Definition

Amount of amortization expense attributable to debt issuance costs.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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- Definition

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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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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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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Description of the frequency of periodic payments (monthly, quarterly, annual).

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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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No definition available.

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

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Percentage of principal amount of debt redeemed.

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No definition available.

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- Definition

Amount of unamortized debt discount (premium) and debt issuance costs.

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

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Amount of the cost of borrowed funds accounted for as interest expense.

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The number of issuer's shares to which the option contract is indexed.

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Exercise or strike price stated in the contract for options indexed to the issuer's equity shares.

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Long-Term Debt - Convertible Senior Notes Due 2026 (Details)	3 Months Ended
	Mar. 31, 2021 USD ($) $ / shares shares	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Principal amount	$ 346,551,000		$ 404,732,000
Interest expense	6,112,000	$ 7,394,000
Amortization of debt issuance costs	810,000	$ 833,000
Convertible Senior Notes Maturing February 2026
Debt Instrument [Line Items]
Principal amount	$ 200,000,000		200,000,000
Interest rate (as a percent)	6.75%
Maturity date	Feb. 15, 2026
Frequency of periodic payment	semi-annually
Initial conversion ratio	0.1433795
Aggregate number of shares \| shares	28,675,900
Initial conversion price per share (USD per share) \| $ / shares	$ 6.97
Increase in the conversion rate	0.0645207
Redemption price as a percentage of principal amount	100.00%
Unamortized debt discount and debt issuance costs			$ 47,300,000
Unamortized debt issuance costs	$ 6,800,000
Effective interest rate (as a percent)	7.60%		12.40%
Interest expense	$ 3,700,000
Coupon interest expense	3,400,000
Amortization of debt issuance costs	$ 300,000
Convertible Senior Notes Maturing February 2026 \| 2026 Capped Calls
Debt Instrument [Line Items]
Aggregate number of common shares subject to capped calls \| shares	28,675,900
Initial strike price \| $ / shares	$ 6.97
Initial cap price \| $ / shares	$ 8.42
Aggregate cost of capped call transactions	$ 10,600,000
Convertible Senior Notes Maturing February 2026 \| Minimum
Debt Instrument [Line Items]
Percentage of closing price of common stock to conversion price	130.00%
Number of trading days	5
Number of consecutive trading days	10
Convertible Senior Notes Maturing February 2026 \| Maximum
Debt Instrument [Line Items]
Percentage of closing price of common stock to conversion price	97.00%
Number of trading days	20
Number of consecutive trading days	30