SHAREHOLDER’S EQUITY - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands				12 Months Ended		15 Months Ended
	May 04, 2021	Feb. 24, 2020	Nov. 18, 2019	Sep. 30, 2021	Sep. 30, 2020	Feb. 24, 2020
Accelerated Share Repurchases [Line Items]
Authorized share repurchase amount	$ 1,000,000,000
Share repurchase program, authorization period	36 months
Number of shares repurchased (in shares)				1,600	6,200
Total repurchase amount					$ 239,800,000
Average price per share (in dollars per share)				$ 81.43	$ 58.57
ASR
Accelerated Share Repurchases [Line Items]
Accelerated share repurchase amount			$ 125,000,000
Number of shares repurchased (in shares)		300	1,700	0	2,000	2,000
Percentage of company total shares			85.00%
Total repurchase amount		$ 18,500,000	$ 106,300,000
Adjustment to additional paid-in capital			$ 18,700,000
Average price per share (in dollars per share)				$ 0	$ 61.47	$ 61.59