Segment Information and Major Customers Summary of Operating Results by Segment (Details) $ in Thousands	12 Months Ended
Sep. 30, 2017 USD ($) segment	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment	2
Revenue	$ 181,634	$ 203,005	$ 203,847
Operating income (loss)	8,807	17,105	10,889
Depreciation and amortization	5,497	4,584	5,347
M2M
Segment Reporting Information [Line Items]
Revenue	174,237	202,294	203,847
Operating income (loss)	12,804	18,822	10,889
Depreciation and amortization	3,575	4,040	5,347
Solutions
Segment Reporting Information [Line Items]
Revenue	7,397	711	0
Operating income (loss)	(3,997)	(1,717)	0
Depreciation and amortization	$ 1,922	$ 544	$ 0

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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