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

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Amount of transactions with related party during the financial reporting period.

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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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Related Party Transactions - Transactions with Joint Ventures (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2015
Related Party Transaction [Line Items]
Other income, net	$ (395)	$ (95)	$ (501)	$ (189)
Doosan-PSI, LLC \| Corporate Joint Venture
Related Party Transaction [Line Items]
Investment amount with related party					$ 1,000
Percent of noncontrolling interest					50.00%