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CUSTOMER CONCENTRATIONS (Details) $ in Millions | 12 Months Ended
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Jan. 31, 2019 USD ($) Owner customer | Jan. 31, 2018 USD ($) Owner customer | Jan. 31, 2017 customer
Customer Concentrations |  |  |
Amounts retained by project owners |  | $ 69.7 |
Percentage of amounts retained by project owners | 93.00% | 99.00% |
Accounts Receivable |  |  |
Customer Concentrations |  |  |
Number of project owners | Owner | 5 | 5 |
Major Customer One |  |  |
Customer Concentrations |  |  |
Amounts retained by project owners | $ 5.8 | $ 19.3 |
Major Customer One | Accounts Receivable |  |  |
Customer Concentrations |  |  |
Percentage of consolidated accounts receivable accounted by major customer | 25.00% | 17.00% |
Major Customer Two |  |  |
Customer Concentrations |  |  |
Amounts retained by project owners | $ 4.5 | $ 18.7 |
Major Customer Two | Accounts Receivable |  |  |
Customer Concentrations |  |  |
Percentage of consolidated accounts receivable accounted by major customer | 15.00% | 17.00% |
Major Customer Three |  |  |
Customer Concentrations |  |  |
Amounts retained by project owners | $ 1.6 | $ 14.1 |
Major Customer Four |  |  |
Customer Concentrations |  |  |
Amounts retained by project owners | 1.3 | 13.4 |
Major Customer Five |  |  |
Customer Concentrations |  |  |
Amounts retained by project owners | $ 1.0 | $ 3.2 |
Power Services | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments | 76.00% | 91.00% | 87.00%
Number of major power industry service customers | customer | 4 | 4 | 5
Power Services | Major Customer One | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments | 16.00% | 29.00% | 20.00%
Power Services | Major Customer Two | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments | 14.00% | 26.00% | 18.00%
Power Services | Major Customer Three | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments | 12.00% | 15.00% | 17.00%
Power Services | Major Customer Four | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments | 10.00% | 14.00% | 14.00%
Power Services | Major Customer Five | Revenue |  |  |
Customer Concentrations |  |  |
Percentage of major customers or segments |  |  | 10.00%

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