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- Definition

Amount of income related to nonoperating activities, classified as other.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Topic 220
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-Section S99
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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
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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.

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Related Party Transactions (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2015
Related Party Transaction [Line Items]
Other income, net	$ 44	$ 395	$ 255	$ 501
Corporate Joint Venture \| Doosan-PSI, LLC
Related Party Transaction [Line Items]
Investment amount with related party					$ 1,000
Percent of noncontrolling interest					50.00%
Maximum
Related Party Transaction [Line Items]
Other income, net	$ 100