SUPPLEMENTAL CASH FLOW INFORMATION (Supplemental Information Referable to Condensed Consolidated Statements of Cash Flows) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
SUPPLEMENTAL CASH FLOW INFORMATION [Abstract]
Interest (exclusive of amount capitalized)		$ 138.0	$ 129.2	$ 129.2
Income taxes		127.9	95.9	56.8
Accrued liabilities for purchases of property, plant & equipment		71.4	55.9	57.3
Recognition of new and revised asset retirement obligations (AROs)		17.1	73.2	(13.9)
Recognition of new and revised right-of-use (ROU) assets for: Operating lease liabilities	[1]	106.9	49.6	444.5
Recognition of new and revised right-of-use (ROU) assets for: Finance lease liabilities	[1]	13.3	6.6	1.2
Amounts referable to business acquisitions, Debt assumed		443.7	0.0	0.0
Amounts referable to business acquisitions,Other liabilities assumed		243.8	5.9	4.4
Amounts referable to business acquisitions, Consideration payable to seller		0.0	9.0	0.0
Amounts referable to business acquisitions, Fair value of noncash assets and liabilities exchanged		0.0	21.2	0.0
Debt issued for purchases of property, plant & equipment		$ 0.0	$ 2.6	$ 0.0

[1] Excludes amounts acquired in business acquisitions. Additionally, the 2019 lease amount includes the initial right-of-use assets resulting from our adoption of ASU 2016-02, “Leases.”