EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 2023	Jun. 30, 2022
Earnings Per Share [Abstract]
Net income	$ 1,532	$ 110,247	$ 115,921	$ 13,053	$ 96,035	$ 111,312	$ 227,700	$ 220,400
Basic earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	97,168			96,154			96,849	96,055
Basic earnings per common share (usd per share)	$ 0.02			$ 0.14			$ 2.35	$ 2.29
Diluted earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	97,168			96,154			96,849	96,055
Incremental shares (in shares)	718			466			689	472
Weighted average shares of common stock outstanding-diluted (in shares)	97,886			96,620			97,538	96,527
Diluted earnings per common share (usd per share)	$ 0.02			$ 0.14			$ 2.33	$ 2.28