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DESCRIPTION OF THE BUSINESS AND BASIS OF PRESENTATION (Details) - USD ($) $ in Thousands	6 Months Ended
	Jul. 31, 2017	Jul. 31, 2016
Description of the Business
Unapproved change orders contract amount	$ 0
Power Services | Minimum
Description of the Business
Revenue recognition period	1 month
Power Services | Maximum
Description of the Business
Revenue recognition period	3 years
GPS
Description of the Business
Consolidated revenues by subsidiaries	89.00%	84.00%

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- Definition

Represents the entity's revenue contributed to the parent entity as a percentage of the parent entity's total revenue.

+ References

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- Definition

Revenue recognition period.

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- Definition

Schedule Of Description Of Business [Line Items]

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- Definition

The contract amount of unapproved change orders.

+ References

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+ Details

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