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REVENUES FROM CONTRACTS WITH CUSTOMERS - Accounting for the Loss Subcontract (Details) - TeesREPProject - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Apr. 30, 2021 | Apr. 30, 2020 | Jan. 31, 2021 | Jan. 31, 2020 | Mar. 24, 2020
REVENUES FROM CONTRACTS WITH CUSTOMERS |  |  |  |  |
Loss recorded |  | $ 2.7 |  | $ 33.6 |
Reversal of profit |  |  |  | $ 0.7 |
Excess of projected project costs over projected project revenues |  | $ 36.2 |  |  |
Percentage of completion of subcontracted work |  |  |  |  | 90.00%
Subcontract loss | $ 29.5 |  |  |  |
The total amounts of accounts receivable and contract assets with the customer | $ 1.6 |  | $ 4.7 |  |

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- Definition 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 + Details
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