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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 8,800		$ 8,800		$ 15,500
Revenue from Contract with Customer, Excluding Assessed Tax	2,067,245	$ 2,000,159	6,165,154	$ 5,682,375
Cost of goods sold	1,670,037	1,614,814	4,988,103	4,580,896
Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	723,869	722,227	2,243,590	2,111,813
Construction [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	686,165	674,996	2,007,708	1,870,406
Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	345,937	312,501	998,438	861,162
Commercial, Institutional and Government [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	311,274	290,435	915,418	838,994
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,525,393	1,473,016	4,571,533	4,267,684
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	541,852	527,143	1,593,621	1,414,691
Shipping and Handling [Member]
Disaggregation of Revenue [Line Items]
Cost of goods sold	$ 18,800	$ 15,500	$ 55,600	$ 43,200