Derivative liabilities and changes in fair value.

No definition available.

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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 increase (decrease) in the value of a contingent consideration liability, including, but not limited to, differences arising upon settlement.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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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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-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

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

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-Publisher FASB
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-Topic 210
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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- Definition

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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- Definition

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

+ References

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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	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2019	Nov. 30, 2017	Mar. 31, 2021	Dec. 31, 2020	May 27, 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	5,900,000			5,900,000
Carrying value of convertible senior notes	$ 638,165,000			$ 638,165,000	$ 441,514,000
0% Convertible Senior Notes Due March 15, 2026
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Fair value of convertible senior notes	369,000,000.0			369,000,000.0
Carrying value of convertible senior notes	$ 263,100,000			$ 263,100,000
Debt instrument, interest rate	0.00%			0.00%
Debt instrument, maturity date	Mar. 15, 2026
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	$ 585,000,000.0			$ 585,000,000.0	663,600,000
Carrying value of convertible senior notes	$ 373,700,000			$ 373,700,000	369,000,000.0
Debt instrument, interest rate	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	$ 7,200,000			$ 7,200,000	265,500,000
Carrying value of convertible senior notes	$ 1,400,000			$ 1,400,000	72,500,000
Debt instrument, interest rate	1.50%		1.50%	1.50%
Debt instrument, maturity date			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
Techwan SA \| Other Expense, Net
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Derivative liabilities, changes in fair value				$ 200,000
One2Many Group B.V.
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Increase (Decrease) in contingent consideration obligation				(700,000)
SnapComms Limited
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Increase (Decrease) in contingent consideration obligation				700,000
Fair Value Measurements, Nonrecurring
Fair Value Liabilities Measured On Recurring Basis Unobservable Input Reconciliation [Line Items]
Asset impairment charges				$ 0	$ 0