Supplemental Disclosure of Cash Flow Information - Schedule of Supplemental Disclosure of Cash Flow Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Cash paid during the period for:
Income taxes, net	$ 5,133	$ 2,569	$ 4,434
Interest	$ 12,601	$ 8,925	$ 7,814