Goodwill and Other Intangible Assets - Intangible Assets, Net - Additional Information (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2020	Mar. 31, 2019
Goodwill And Intangible Assets Disclosure [Abstract]
Impairment of long-lived asset			$ 0
Amortization expense related to intangible assets	$ 5,400,000	$ 5,200,000	10,600,000	$ 10,500,000
Expected amortization of intangible assets for remainder of 2020	$ 10,200,000		$ 10,200,000