EARNINGS (LOSSES) PER COMMON SHARE - Schedule of Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Numerator:
Net income	$ 54,772	$ 95,173
Adjustment for basic earnings per share
Earnings allocated to unvested shareholders	(760)	(1,248)
Numerator for basic earnings per share	54,012	93,925
Adjustment for diluted earnings per share
Effect of reallocating undistributed earnings of unvested shareholders	1	2
Numerator for diluted earnings per share	$ 54,013	$ 93,927
Denominator:
Denominator for basic earnings per share - weighted-average shares (in shares)	98,867	99,143
Effect of dilutive shares from stock options, restricted stock and performance share units (in shares)	292	485
Denominator for diluted earnings (loss) per share - adjusted weighted-average shares (in shares)	99,159	99,628
Basic earnings per common share (in dollars per share)	$ 0.55	$ 0.95
Diluted earnings per common share (in dollars per share)	$ 0.54	$ 0.94

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Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders.

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