Derivative liabilities and changes in fair value.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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- Definition

Amount of liability recognized arising from contingent consideration in a business combination, expected to be settled within one year or the normal operating cycle, if longer.

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- Definition

Aggregate number of common shares reserved for future issuance.

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- Definition

Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

No definition available.

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- Definition

Carrying amount of long-term convertible debt as of the balance sheet date, net of the amount due in the next twelve months or greater than the normal operating cycle, if longer. The debt is convertible into another form of financial instrument, typically the entity's common stock.

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- Definition

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

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- Definition

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

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

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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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Fair Value Measurements - Additional Information (Details) - USD ($)	1 Months Ended		3 Months Ended	9 Months Ended	12 Months Ended
	Dec. 31, 2019	Nov. 30, 2017	Sep. 30, 2020	Sep. 30, 2020	Dec. 31, 2019	May 27, 2020	Mar. 19, 2020
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Asset impairment charges				$ 0
Fair value of assets transferred from level 1 to level 2			$ 0	0
Fair value of assets transferred from level 2 to level 1			0	0
Fair value of liabilities transferred from level 1 to level 2			0	0
Fair value of liabilities transferred from level 2 to level 1			$ 0	$ 0
Common stock reserved for future issuance			5,000,000.0	5,000,000.0
Contingent consideration			$ 7,996,000	$ 7,996,000
Carrying value of convertible senior notes	$ 430,282,000		445,915,000	445,915,000	$ 430,282,000
0.125% Convertible Senior Notes Due 2024
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of convertible senior notes	450,400,000		596,700,000	596,700,000	450,400,000
Carrying value of convertible senior notes	$ 351,100,000		$ 364,500,000	$ 364,500,000	$ 351,100,000
Debt instrument, interest rate	0.125%		0.125%	0.125%	0.125%
Debt instrument, maturity date	Dec. 15, 2024			Dec. 15, 2024
1.50% Convertible Senior Notes Due 2022
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of convertible senior notes	$ 215,800,000		$ 364,000,000.0	$ 364,000,000.0	$ 215,800,000
Carrying value of convertible senior notes	$ 79,200,000		$ 81,500,000	$ 81,500,000	79,200,000
Debt instrument, interest rate		1.50%	1.50%	1.50%
Debt instrument, maturity date		Nov. 01, 2022		Nov. 01, 2022
Techwan SA
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Common stock reserved for future issuance						6,779
Contingent consideration			$ 100,000	$ 100,000		$ 2,030,000
Techwan SA \| Other Expense, Net
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative liabilities and changes in fair value			100,000
One2Many Group B.V.
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Contingent consideration			$ 1,400,000	1,400,000			$ 2,190,000
Fair Value Measurements, Nonrecurring
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Asset impairment charges				$ 0	$ 0