CONTINGENCIES (Details) $ in Millions		1 Months Ended		12 Months Ended
	Feb. 01, 2016 USD ($) project	Jul. 31, 2018 USD ($)	Jun. 30, 2018 USD ($)	Jan. 31, 2019 USD ($)	Jan. 31, 2018 USD ($)
GPS
Loss Contingencies
Outstanding surety bonds				$ 11.1	$ 11.1
Minimum
Loss Contingencies
Warranty period				9 months
Maximum
Loss Contingencies
Warranty period				24 months
PPS Engineers, Inc. claims lawsuit
Loss Contingencies
Amount paid on settlement		$ 0.9
Gain on settlement				$ 1.4
Former subcontractor | GPS
Loss Contingencies
Amount of arbitration panel awarded			$ 5.2
Pending Litigation | PPS Engineers, Inc. claims lawsuit
Loss Contingencies
Amount of damages sought by plaintiff	$ 2.3
Number of significant project locations involved in the lawsuit | project	1