CONDENSED FINANCIAL INFORMATION OF REGISTRANT (PARENT COMPANY ONLY) - Schedule of Statements of Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2022
Condensed Statement of Income Captions [Line Items]
Comprehensive income	$ 149,819	$ 64,239	$ 67,158
Parent Company
Condensed Statement of Income Captions [Line Items]
Net income of subsidiaries	153,379	62,361	67,158
Comprehensive income	$ 149,819	$ 64,239	$ 67,158