Supplemental Disclosure of Cash Flow Information - Schedule of Supplemental Disclosure of Cash Flow Information (Parenthetical) (Detail) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Jul. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Supplemental Cash Flow Elements [Abstract]
Tax payments	$ 8,500	$ 16,051	$ 9,988	[1]

[1] In July 2020, the Company made $8.5 million in tax payments that were deferred from April and June.