COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS (Details) - USD ($) $ in Thousands	Jan. 31, 2017	Jan. 31, 2016
COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS
Costs charged to uncompleted contracts	$ 485,629	$ 764,071
Estimated accrued earnings	78,708	116,326
Contracts Receivables, Gross	564,337	880,397
Less - billings to date	770,386	982,182
Costs and estimated earnings in excess of billings	3,192	4,078
Billings in excess of costs and estimated earnings	209,241	105,863
Billings in excess of costs and estimated earnings on uncompleted contracts, net	(206,049)	$ (101,785)
Retention payable	$ 17,200