COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS (Details) - USD ($) $ in Thousands	Apr. 30, 2016	Jan. 31, 2016
COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS
Costs incurred on uncompleted contracts	$ 807,310	$ 764,071
Estimated accrued earnings	135,577	116,326
Contracts Receivables, Gross	942,887	880,397
Less - billings to date	1,073,431	982,182
Billings in excess of costs and estimated earnings on uncompleted contracts, net	(130,544)	(101,785)
Costs and estimated earnings in excess of billings	4,077	4,078
Billings in excess of costs and estimated earnings	134,621	$ 105,863
Retention payable	$ 10,300