Number of entity's patents that another entity has allegedly infringed.

No definition available.

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
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-Paragraph 9
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-Publisher FASB
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-Section 50
-Paragraph 4
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-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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- Definition

The total number of new claims filed pertaining to a loss contingency during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349

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- Definition

Number of another entity's patents that the entity has allegedly infringed.

+ References

No definition available.

+ Details

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Commitments and Contingencies - Additional Information (Details)				3 Months Ended	6 Months Ended
	Sep. 08, 2017 USD ($)	Nov. 02, 2016 patent	Apr. 21, 2016 patent	Mar. 31, 2018 USD ($) claim	Nov. 02, 2016 patent
Siemens Industry, Inc. \| Pending Litigation
Loss Contingencies [Line Items]
Patents allegedly infringed \| patent		6	7		10
Patents violated \| patent					3
Subsidiaries \| Denver Transit \| Threatened Litigation
Loss Contingencies [Line Items]
Number of claims filed (claims) \| claim				0
Subsidiaries \| Denver Transit, Delivery of Train Management System \| Threatened Litigation
Loss Contingencies [Line Items]
Damages alleged \| $				$ 0
Subsidiaries \| Denver Transit, Installation of Constant Wireless Crossings \| Threatened Litigation
Loss Contingencies [Line Items]
Damages alleged \| $	$ 36,800,000