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CUSTOMER CONCENTRATIONS (Details) $ in Millions | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jul. 31, 2018 USD ($) customer | Jul. 31, 2017 customer | Jul. 31, 2018 USD ($) Owner customer | Jul. 31, 2017 customer | Jan. 31, 2018 USD ($) Owner
Customer Concentrations |  |  |  |  |
Amounts retained by project owners | $ 23.4 |  | $ 23.4 |  | $ 69.7
Percentage of amounts retained by project owners |  |  | 87.00% |  | 99.00%
Accounts Receivable |  |  |  |  |
Customer Concentrations |  |  |  |  |
Number of project owners | Owner |  |  | 3 |  | 5
Major Customer One |  |  |  |  |
Customer Concentrations |  |  |  |  |
Amounts retained by project owners | 14.2 |  | $ 14.2 |  | $ 19.3
Major Customer One | Accounts Receivable |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of consolidated accounts receivable accounted by major customer |  |  | 19.00% |  | 18.00%
Major Customer Two |  |  |  |  |
Customer Concentrations |  |  |  |  |
Amounts retained by project owners | 5.0 |  | $ 5.0 |  | $ 18.7
Major Customer Two | Accounts Receivable |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of consolidated accounts receivable accounted by major customer |  |  | 13.00% |  | 18.00%
Major Customer Three |  |  |  |  |
Customer Concentrations |  |  |  |  |
Amounts retained by project owners | $ 1.2 |  | $ 1.2 |  | $ 14.1
Major Customer Four |  |  |  |  |
Customer Concentrations |  |  |  |  |
Amounts retained by project owners |  |  |  |  | 13.4
Major Customer Five |  |  |  |  |
Customer Concentrations |  |  |  |  |
Amounts retained by project owners |  |  |  |  | $ 3.2
Power Services | Revenue |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of major customers or segments | 77.00% | 92.00% | 82.00% | 92.00% |
Number of major power industry service customers | customer | 4 | 4 | 3 | 4 |
Power Services | Major Customer One | Revenue |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of major customers or segments | 18.00% | 31.00% | 20.00% | 28.00% |
Power Services | Major Customer Two | Revenue |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of major customers or segments | 16.00% | 27.00% | 14.00% | 26.00% |
Power Services | Major Customer Three | Revenue |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of major customers or segments | 11.00% | 17.00% | 13.00% | 19.00% |
Power Services | Major Customer Four | Revenue |  |  |  |  |
Customer Concentrations |  |  |  |  |
Percentage of major customers or segments | 10.00% | 13.00% |  | 15.00% |

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