Name:	evbg_ShareBasedCompensationArrangementByShareBasedPaymentAwardIncreaseInNumberOfSharesReservedAndAvailableForIssuance
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

Aggregate number of common shares reserved for future issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Data Type:	xbrli:sharesItemType
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Period Type:	instant

Discount rate from fair value on offering date that participants pay for shares.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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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.

No definition available.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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Number of share instruments newly issued under a share-based compensation plan.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

Purchase price of common stock expressed as a percentage of its fair value.

No definition available.