Fair Value Measurements (Details) - USD ($) $ in Thousands		3 Months Ended			9 Months Ended
	Oct. 05, 2015	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Jun. 30, 2021	Jun. 30, 2020	Mar. 31, 2021	Mar. 26, 2021	Mar. 31, 2020	Dec. 13, 2019
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Payment for contingent consideration					$ 5,772	$ (128)
Goodwill		$ 221,331	$ 210,135		221,331
Fair Value, Inputs, Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration fair value		5,900	4,228	$ 5,407	5,900	$ 4,228	$ 8,000		$ 10,379
Contingent Consideration | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration fair value		0	0		0
Contingent Consideration | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration fair value		0	0		0
Contingent Consideration | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration fair value		5,900	4,228		5,900
Bluenica Corporation
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Earn-out payment installment period	4 years
Bluenica Corporation | Contingent Consideration
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Payment for contingent consideration			2,900
Accelerated | Contingent Consideration
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Payment for contingent consideration			2,400	$ 3,500
Opengear
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Goodwill										$ 57,088
Opengear | Contingent Consideration
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Payment for contingent consideration		10,000	900
Haxiot
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Goodwill								$ 8,617
Estimate of Fair Value Measurement | Contingent Consideration | Fair Value, Measurements, Recurring
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Contingent consideration fair value		5,900	$ 4,228		5,900
Estimate of Fair Value Measurement | Haxiot | Contingent Consideration | Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Fair Value Inputs, Liabilities, Quantitative Information [Line Items]
Goodwill		8,600			8,600
Contingent consideration fair value		$ 5,900			$ 5,900