Segment Information and Major Customers Summary of Operating Results by Segment (Details) $ in Thousands	12 Months Ended
Sep. 30, 2021 USD ($) segment	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Segment Reporting [Abstract]
Number of reportable segments \| segment	2
Number of operating segments \| segment	4
Segment Reporting Information [Line Items]
Revenue	$ 308,632	$ 279,271	$ 254,203
Gross profit	166,657	143,972	119,035
Operating income (loss)	10,528	11,317	10,072
Depreciation and amortization	20,877	19,299	13,396
IoT Products & Services
Segment Reporting Information [Line Items]
Revenue	264,173	249,530	215,287
Gross profit	144,472	129,349	100,522
Operating income (loss)	18,212	27,216	21,806
Depreciation and amortization	13,109	11,521	6,102
IoT Solutions
Segment Reporting Information [Line Items]
Revenue	44,459	29,741	38,916
Gross profit	22,185	14,623	18,513
Operating income (loss)	(7,684)	(15,899)	(11,734)
Depreciation and amortization	$ 7,768	$ 7,778	$ 7,294

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