Represents the debt instrument principal and unpaid interest payable upon events of default.

No definition available.

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Debt Instrument Additional Amount Available For Repurchase

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Threshold period of specified business days within which the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day triggers the conversion feature.

+ References

No definition available.

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Threshold period of specified consecutive trading days within which the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day triggers the conversion feature.

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No definition available.

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Represents the maximum product of the closing sale price of shares of the entity's common stock and the applicable conversion rate for such trading day.

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No definition available.

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Represents the minimum percentage of debt principal amount by instrument holders.

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No definition available.

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Amount of net deferred tax liability attributable to taxable temporary differences from issuance of convertible debt instruments.

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Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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-Name Accounting Standards Codification
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-SubTopic 10
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-Subparagraph (g)(2)
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Adjustment to additional paid in capital resulting from the recognition of convertible debt instruments as two separate components - a debt component and an equity component. This bifurcation may result in a basis difference associated with the liability component that represents a temporary difference for purposes of applying accounting for income taxes. The initial recognition of deferred taxes for the tax effect of that temporary difference is as an adjustment to additional paid in capital.

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-SubTopic 20
-Section 25
-Paragraph 22
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Amount of noncash expense included in interest expense to amortize debt discount and premium associated with the related debt instruments. Excludes amortization of financing costs. Alternate captions include noncash interest expense.

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

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- Definition

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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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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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

Cumulative amount paid into a fund, which is used to retire the debt instrument.

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- Definition

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

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
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- Definition

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

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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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-Paragraph 3
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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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- Definition

Amount, after accumulated amortization, of debt discount.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt - Narrative (Details)		1 Months Ended		3 Months Ended	9 Months Ended
Debt - Narrative (Details)	Jan. 01, 2021 USD ($)	Sep. 30, 2019 USD ($) D $ / shares	Aug. 31, 2015 USD ($) D $ / shares	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)	Jan. 31, 2020 $ / shares
Long-term debt
Long-term debt					$ 281,604,000		$ 309,145,000
Current portion of long-term debt					149,358,000
Conversion price per share (in dollars per share) \| $ / shares								$ 6.00
Additional paid-in capital					2,092,534,000		2,171,746,000
1.50% Convertible senior notes due 2026
Long-term debt
Term of the convertible notes	7 years
Debt discount to be amortized	$ 0
3.00% Convertible senior notes due 2022
Long-term debt
Term of the convertible notes	7 years
Debt discount to be amortized	$ 0
Convertible debt \| 1.50% Convertible senior notes due 2026
Long-term debt
Net carrying amount					281,604,000		177,377,000
Debt principal amount		$ 287,500,000			$ 287,500,000		287,500,000
Debt instrument additional amount available for repurchase		$ 37,500,000
Interest rate ( as a percent )		1.50%			1.50%
Net proceeds from issuance of convertible notes		$ 279,300,000
Trading days, number \| D		20
Consecutive trading days, period \| D		30
Stock price trigger		130.00%
Business days, period		5 days
Consecutive trading-day period		5 days
Maximum product of the closing sale price of shares of the Company's common stock and the applicable conversion rate for such trading day		98.00%
Conversion ratio		19.0404
Conversion price per share (in dollars per share) \| $ / shares		$ 52.52
Convertible instruments principal and unpaid interest payable upon events of default		100.00%
Minimum percentage of principal held by convertible debt instrument holders required to issue notice for declaration of principal and unpaid interest payable upon events of default		25.00%
Term of the convertible notes		7 years	7 years		5 years
Equity component of convertible notes, net		$ 123,000,000.0
Amortization of debt discount				$ 3,313,000		$ 9,786,000
Debt discount to be amortized							106,065,000
Net deferred tax liability in connection with convertible notes					$ 25,300,000
Fair value of convertible notes					294,900,000		394,900,000
Convertible debt \| 1.50% Convertible senior notes due 2026 \| Redemption on or after September 20, 2023
Long-term debt
Trading days, number \| D		19
Consecutive trading days, period \| D		30
Stock price trigger		130.00%
Redemption price as percent of principal amount		100.00%
Sinking fund		$ 0
Convertible debt \| 3.00% Convertible senior notes due 2022
Long-term debt
Net carrying amount					149,358,000		131,763,000
Debt principal amount			$ 150,000,000.0		150,000,000		150,000,000
Interest rate ( as a percent )			3.00%
Net proceeds from issuance of convertible notes			$ 145,400,000
Trading days, number \| D			20
Stock price trigger			130.00%
Business days, period			5 days
Consecutive trading-day period			5 days
Maximum product of the closing sale price of shares of the Company's common stock and the applicable conversion rate for such trading day			98.00%
Conversion ratio			17.7487
Conversion price per share (in dollars per share) \| $ / shares			$ 56.34
Convertible instruments principal and unpaid interest payable upon events of default			100.00%
Minimum percentage of principal held by convertible debt instrument holders required to issue notice for declaration of principal and unpaid interest payable upon events of default			25.00%
Term of the convertible notes			7 years
Equity component of convertible notes, net			$ 57,500,000
Amortization of debt discount				$ 2,372,000		$ 6,892,000
Debt discount to be amortized							17,372,000
Net deferred tax liability in connection with convertible notes			$ 22,300,000
Fair value of convertible notes					$ 155,500,000		193,200,000
Remaining contractual life of the convertible notes					10 months 24 days
Convertible debt \| 3.00% Convertible senior notes due 2022 \| Redemption on or after August 20, 2018
Long-term debt
Trading days, number \| D			19
Consecutive trading days, period \| D			30
Stock price trigger			130.00%
Redemption price as percent of principal amount			100.00%
Sinking fund			$ 0
Cumulative Effect Adjustment
Long-term debt
Long-term debt							$ 120,400,000
Cumulative Effect Adjustment \| 1.50% Convertible senior notes due 2026
Long-term debt
Additional paid-in capital	(123,000,000.0)
Amortization of debt discount	16,100,000
Cumulative Effect Adjustment \| 3.00% Convertible senior notes due 2022
Long-term debt
Additional paid-in capital	(57,500,000)
Amortization of debt discount	$ 38,700,000