REVENUES FROM CONTRACTS WITH CUSTOMERS - Accounting for the Loss Subcontract (Details) - TeesREPProject - USD ($) $ in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Jul. 31, 2020	Jul. 31, 2021	Jul. 31, 2020	Jan. 31, 2021	Mar. 24, 2020
REVENUES FROM CONTRACTS WITH CUSTOMERS
Excess of projected project costs over projected project revenues			$ 32.3
Percentage of completion of subcontracted work					90.00%
Subcontract loss		$ 29.5
Adjustments in the amount made to the APC	$ 2.3
Adjustments in the amount made to the APC			$ 0.4
The total amounts of accounts receivable and contract assets with the customer				$ 4.7
Maximum
REVENUES FROM CONTRACTS WITH CUSTOMERS
The total amounts of accounts receivable and contract assets with the customer		$ 0.1