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REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
REVENUE (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Deferred Revenue	$ 10,400		$ 10,400		$ 11,800
Revenue from Contract with Customer, Excluding Assessed Tax	2,150,088	$ 2,103,994	4,111,355	$ 4,097,909
Cost of goods sold	1,741,114	1,704,100	3,319,886	3,318,066
Industrial [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	761,934	760,741	1,498,825	1,519,723
Construction [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	704,183	683,752	1,337,483	1,321,551
Utility [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	346,941	336,961	655,213	652,506
Commercial, Institutional and Government [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	337,030	322,540	619,834	604,129
UNITED STATES
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	1,616,347	1,563,392	3,077,263	3,046,140
CANADA
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	415,030	405,981	799,700	804,689
Non-US [Member]
Disaggregation of Revenue [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax	118,711	134,621	234,392	247,080
Shipping and Handling [Member]
Disaggregation of Revenue [Line Items]
Cost of goods sold	$ 18,200	$ 18,600	$ 35,200	$ 36,800