EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Net income, as reported	$ 110,247	$ 115,921	$ 96,035	$ 111,312	$ 226,168	$ 207,347
Basic earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	96,893		96,068		96,689	96,006
Basic earnings per common share (usd per share)	$ 1.14		$ 1.00		$ 2.34	$ 2.16
Diluted earnings per share
Weighted average shares of common stock outstanding-basic (in shares)	96,893		96,068		96,689	96,006
Incremental shares (in shares)	663		448		657	474
Weighted average shares of common stock outstanding-diluted (in shares)	97,556		96,516		97,346	96,480
Diluted earnings per common share (usd per share)	$ 1.13		$ 1.00		$ 2.32	$ 2.15