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

No definition available.

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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.

+ References

No definition available.

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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
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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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)				6 Months Ended		30 Months Ended
	Sep. 08, 2017 USD ($)	Nov. 02, 2016 patent	Apr. 21, 2016 patent	Jun. 30, 2018 USD ($) claim	Nov. 02, 2016 patent	Nov. 02, 2018 patent
Siemens Industry, Inc. \| Pending Litigation
Loss Contingencies [Line Items]
Patents allegedly infringed		6	7
Patents allegedly infringed upon					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
Scenario Forecast \| Siemens Industry, Inc. \| Pending Litigation
Loss Contingencies [Line Items]
Patents allegedly infringed						10