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REVENUE RECOGNITION - Update to Significant Accounting Policies (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jul. 31, 2018 | Jul. 31, 2018 | Jan. 31, 2018
Update to Significant Accounting Policies |  |  |
Amounts of unpriced change orders included in transaction prices | $ 4.1 | $ 4.1 | $ 9.3
Minimum |  |  |
Update to Significant Accounting Policies |  |  |
Revenue recognition period |  | 3 months |
Maximum |  |  |
Update to Significant Accounting Policies |  |  |
Revenue recognition period |  | 3 years |
Impact of the Adoption of ASC Topic 606 |  |  |
Update to Significant Accounting Policies |  |  |
Impact on revenues, changes in estimates of the costs-to-complete active contracts | 15.4 | $ 10.8 |
Accounts payable |  |  |
Update to Significant Accounting Policies |  |  |
Amounts retained from vendors and subcontractors by the Company | $ 35.1 | $ 35.1 | $ 38.7

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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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82913847&loc=SL49130551-203045 + Details
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