COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS (Details) - USD ($) $ in Thousands	Oct. 31, 2017	Jan. 31, 2017
COSTS, ESTIMATED EARNINGS AND BILLINGS ON UNCOMPLETED CONTRACTS
Costs charged to uncompleted contracts	$ 1,074,974	$ 485,629
Estimated accrued earnings	177,065	78,708
Contracts receivables, gross	1,252,039	564,337
Less - billings to date	1,388,705	770,386
Billings in excess of costs and estimated earnings on uncompleted contracts, net	(136,666)	(206,049)
Costs and estimated earnings in excess of billings	10,197	3,192
Billings in excess of costs and estimated earnings	146,863	209,241
Retention payable	$ 34,600	$ 17,200