Goodwill and Intangible Assets - Summary of Changes to Goodwill (Detail) $ in Thousands	6 Months Ended
	Mar. 31, 2022 USD ($)
Goodwill [Roll Forward]
Balance at September 30, 2021	$ 788,185
Foreign currency translation adjustment	(4,441)
Balance at March 31, 2022	783,744
Scores
Goodwill [Roll Forward]
Balance at September 30, 2021	146,648
Foreign currency translation adjustment	0
Balance at March 31, 2022	146,648
Software
Goodwill [Roll Forward]
Balance at September 30, 2021	641,537
Foreign currency translation adjustment	(4,441)
Balance at March 31, 2022	$ 637,096