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

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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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 Details (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
Acquisitions Details (Details) - USD ($) $ in Thousands	Dec. 13, 2019	Jun. 30, 2020	Sep. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2020	Dec. 31, 2019
Business Acquisition [Line Items]
Change in fair value of contingent consideration				$ (128)	$ 1,188
Operating lease right-of-use assets		$ 14,937	$ 0	14,937
Operating lease liability		16,799	0	16,799
Opengear
Business Acquisition [Line Items]
Cash paid at closing	$ 148,058
Weighted average useful life identifiable intangibles	13 years 4 months 24 days
Opengear \| General and Administrative
Business Acquisition [Line Items]
Acquisition costs			300	2,600
Earn-Out Payments \| Maximum \| Opengear
Business Acquisition [Line Items]
Earn-out payment maximum							$ 5,000
Earn-Out Payments \| Maximum \| Forecast \| Opengear
Business Acquisition [Line Items]
Earn-out payment maximum						$ 10,000
Customer Relationships \| Opengear
Business Acquisition [Line Items]
Useful life identifiable intangibles	14 years 6 months
Purchased and Core Technology \| Opengear
Business Acquisition [Line Items]
Useful life identifiable intangibles	9 years
Trademarks \| Opengear
Business Acquisition [Line Items]
Useful life identifiable intangibles	12 years
Other non-current assets \| Opengear
Business Acquisition [Line Items]
Operating lease right-of-use assets	$ 1,400
Other current and non-current liabilities \| Opengear
Business Acquisition [Line Items]
Operating lease liability	1,700
Contingent Consideration \| Opengear
Business Acquisition [Line Items]
Change in fair value of contingent consideration		900
Estimate of Fair Value Measurement \| Fair Value, Measurements, Recurring \| Contingent Consideration
Business Acquisition [Line Items]
Contingent consideration fair value		4,228	$ 5,407	4,228
Estimate of Fair Value Measurement \| Fair Value, Measurements, Recurring \| Contingent Consideration \| Opengear
Business Acquisition [Line Items]
Contingent consideration fair value	$ 5,100
Estimate of Fair Value Measurement \| Fair Value, Measurements, Recurring \| Contingent Consideration \| Earn-Out Payments \| Opengear
Business Acquisition [Line Items]
Contingent consideration fair value		$ 4,200		$ 4,200