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REVENUES FROM CONTRACT WITH CUSTOMERS - Accounting for the Loss Subcontract (Details) - TeesREPProject - USD ($) $ in Millions	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020	Mar. 24, 2020
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Loss recorded		$ 33.6
Reversal of profit		0.7
Percentage of completion of subcontracted work			90.00%
Subcontract loss	$ 29.5
The total amounts of accounts receivable and contract assets with the customer	$ 4.7	$ 19.2

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The amount of gain (loss) from subcontract.

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Percentage of completion of the subcontracted work under the project.

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Amount of increase (decrease) in revenue recognized for cumulative catch-up adjustment from change in measure of progress which (increases) decreases obligation to transfer good or service to customer for which consideration from customer has been received or is due.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118956577&loc=SL49130551-203045

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