Increase decrease in accumulated deficit.

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- Definition

Increase (decrease) in additional paid in capital.

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No definition available.

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Increase (decrease) in carrying amount of convertible notes.

+ References

No definition available.

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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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- Definition

The number of equity instruments that the holder of the debt instrument would receive if the debt was converted to equity.

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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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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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- 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.

+ References

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

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Indebtedness - Additional Information (Detail)			3 Months Ended		6 Months Ended
Indebtedness - Additional Information (Detail)	Jan. 02, 2021 USD ($)	Nov. 14, 2017 USD ($) shares $ / shares	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Debt Instrument [Line Items]
Debt instrument, face amount			$ 1,119,993,000		$ 1,119,993,000
ASU 2020-06
Debt Instrument [Line Items]
Increase in convertible notes	$ 96,800,000
Decrease in accumulated deficit	60,200,000
Decrease in additional paid-in-capital	157,000,000.0
Interest expense reduced	5,500,000
2024 Convertible Notes [Member]
Debt Instrument [Line Items]
Debt instrument, face amount		$ 570,000,000.0	$ 569,993,000		$ 569,993,000		$ 569,993,000
Debt instrument, maturity date		Nov. 15, 2024
Debt instrument, interest rate per annum		1.50%
Debt instrument, payment frequency					The 2024 Notes contain customary covenants and events of default, occurrence of which permits the certain holders to accelerate all outstanding obligations, including principal and interest.
Debt issuance costs		$ 10,600,000
Debt instrument, conversion rate		0.013621
Debt instrument, conversion price \| $ / shares		$ 73.42
2024 Convertible Notes [Member] \| ASU 2020-06
Debt Instrument [Line Items]
Increase in convertible notes	96,800,000
Decrease in accumulated deficit	60,200,000
Decrease in additional paid-in-capital	$ 157,000,000.0
Effective interest rate percentage			1.90%		1.90%
Interest expense reduced			$ 2,700,000	$ 7,800,000	$ 5,300,000	$ 15,500,000
Debt Instrument Fair Value			$ 770,400,000		$ 770,400,000
2024 Convertible Notes [Member] \| Common Stock [Member]
Debt Instrument [Line Items]
Debt instrument, convertible into shares \| shares		7,763,552