SUPPLEMENTAL CASH FLOW INFORMATION (Supplemental Information Referable to Condensed Consolidated Statements of Cash Flows) (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019
SUPPLEMENTAL CASH FLOW INFORMATION [Abstract]
Interest (exclusive of amount capitalized)		$ 60,741	$ 66,414
Income taxes		9,055	34,297
Accrued liabilities for purchases of property, plant & equipment		10,994	30,259
Recognition of new asset retirement obligations		0	263
Right-of-use assets obtained in exchange for new operating lease liabilities	[1]	25,083	435,678
Amounts referable to business acquisitions Liabilities assumed		5,637	3,525
Amounts referable to business acquisitions Consideration payable to seller		8,980	0
Fair value of noncash assets and liabilities exchanged		$ 21,214	$ 0

[1] The 2019 amount includes the initial right-of-use assets resulting from our adoption of ASU 2016-02, “Leases.”