OTHER COMPREHENSIVE INCOME (LOSS) (Details) - Total Comprehensive Income (Loss) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net income	$ 125,678	$ 14,912	$ 30,010
Other comprehensive income (loss), net of taxes	26,369	20,760	9,947
Comprehensive income	$ 152,047	$ 35,672	$ 39,957