Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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No definition available.

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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- Definition

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Acquisitions - Acquisition of a Business (Details) - USD ($) $ in Thousands	Dec. 14, 2020	Mar. 31, 2021	Dec. 31, 2020
Business Acquisition [Line Items]
Goodwill		$ 112,838	$ 112,838
Shooter Detection Systems
Business Acquisition [Line Items]
Percentage of business acquired	100.00%
Consideration	$ 26,600
Purchase price adjustment	(100)
Goodwill	7,176
Customer Relationships \| Shooter Detection Systems
Business Acquisition [Line Items]
Intangible assets acquired	$ 2,362
Weighted-average estimated useful life of intangible assets acquired	6 years
Developed Technology \| Shooter Detection Systems
Business Acquisition [Line Items]
Intangible assets acquired	$ 13,522
Weighted-average estimated useful life of intangible assets acquired	7 years
Trade Name \| Shooter Detection Systems
Business Acquisition [Line Items]
Intangible assets acquired	$ 512
Weighted-average estimated useful life of intangible assets acquired	5 years