Subsequent Events (Details) - DP Engineering [Member] $ in Millions		12 Months Ended
Feb. 15, 2019 USD ($)	Dec. 31, 2018 Company
Business Acquisition [Abstract]
Acquisition date		Feb. 15, 2019
Period to satisfy indemnification claims		18 months
Number of large power generation companies \| Company		2
Subsequent Event [Member]
Business Acquisition [Abstract]
Percentage of ownership interest acquired	100.00%
Cash purchase price	$ 13.5
Proceeds from the issuance of debt	14.3
Earn-out amount	5.0
Cash consideration in escrow	$ 1.7

Cash withheld in escrow account

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- Definition

Refers to the number of large power generation companies.

+ References

No definition available.

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- Definition

Period to satisfy indemnification claims after closing.

+ References

No definition available.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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-Name Accounting Standards Codification
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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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- References

No definition available.

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- Definition

For indemnification assets recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the indemnification benefit which may be realized.

+ References

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

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