Goodwill and Other Identifiable Intangible Assets, Net (Goodwill Rollforward) (Details) $ in Thousands	6 Months Ended
Mar. 31, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 210,135
Acquisition	15,095
Adjustment (see Note 2)	846
Foreign currency translation adjustment	1,457
Ending balance	227,533
IoT Solutions Segment
Goodwill [Roll Forward]
Beginning balance	49,770
Acquisition	0
Adjustment (see Note 2)	0
Foreign currency translation adjustment	690
Ending balance	50,460
IoT Products & Services Segment
Goodwill [Roll Forward]
Beginning balance	160,365
Acquisition	15,095
Adjustment (see Note 2)	846
Foreign currency translation adjustment	767
Ending balance	$ 177,073

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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