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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 11,000		$ 11,000		$ 11,800
Revenue from Contract with Customer, Excluding Assessed Tax	2,148,110	$ 2,067,245	6,259,465	$ 6,165,154
Cost of goods sold	1,747,913	1,670,037	5,067,799	4,988,103
Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	755,129	723,869	2,253,974	2,243,590
Construction [Domain]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	714,589	686,165	2,052,061	2,007,708
Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	357,527	345,937	1,012,726	998,438
Commercial, Institutional and Government [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	320,865	311,274	940,704	915,418
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,601,962	1,525,393	4,679,251	4,571,533
CANADA
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	431,233	429,830	1,230,855	1,234,600
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	114,915	112,022	349,359	359,021
Shipping and Handling [Member]
Disaggregation of Revenue [Line Items]
Cost of goods sold	$ 17,600	$ 18,800	$ 52,800	$ 55,600