REVENUES FROM CONTRACTS WITH CUSTOMERS (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2023	Jul. 31, 2022	Jan. 31, 2023
REVENUES FROM CONTRACTS WITH CUSTOMERS
Revenue recognized	$ 64.7	$ 83.2	$ 87.0	$ 127.6
Retained amounts by project owners	$ 28.1		$ 28.1		$ 49.1
Amounts of unpriced change orders included in transaction prices	12.8		12.8		11.6

Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 606
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479806/606-10-50-8

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration