COMMITMENTS - General Information (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2019	Jan. 31, 2018	Jan. 31, 2017
Costs of Revenues
Commitments
Rent incurred on construction projects included in the costs of revenues	$ 11.4	$ 20.3	$ 13.2
Selling, General and Administrative Expenses
Commitments
Rent expense included in selling, general and administrative expenses of continuing operations	0.7	$ 0.7	$ 0.6
TRC
Commitments
Annual lease amount for primary offices and plant	0.3
APC
Commitments
Annual lease amount for primary offices and plant	$ 0.1