Segment Information Total Assets (Details) - USD ($) $ in Thousands		Mar. 31, 2018	Sep. 30, 2017
Segment Reporting, Asset Reconciling Item [Line Items]
Assets		$ 359,336	$ 345,189
IoT Products & Services
Segment Reporting, Asset Reconciling Item [Line Items]
Assets		207,682	182,555
IoT Solutions
Segment Reporting, Asset Reconciling Item [Line Items]
Assets		92,016	47,644
Unallocated
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	[1]	$ 59,638	$ 114,990

[1] Unallocated consists of cash and cash equivalents, current marketable securities and long-term marketable securities.