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FAIR VALUE MEASUREMENTS - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Aug. 13, 2021	Mar. 17, 2021	Oct. 22, 2019	Dec. 15, 2016
Senior Notes \| Senior Notes due 2031 – 4.000%
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate (percent)	4.00%	4.00%		4.00%
Senior Notes \| Senior Notes due 2032 – 4.375%
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate (percent)	4.375%	4.375%	4.375%
Senior Notes \| Senior Notes - 4.500%
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate (percent)	4.50%	4.50%			4.50%
Senior Notes \| Senior Notes due 2026 – 5.250%
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate (percent)	5.25%	5.25%				5.25%
Convertible debt investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cost basis of investment	$ 222.1	$ 193.4
Unrealized loss on investment	(105.1)	(3.1)
Total realized / unrealized gains included in net earnings	$ 3.7	$ 0.3