Goodwill - Summary of Changes to Goodwill (Details) - USD ($)	12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023
Goodwill [Roll Forward]
Beginning Balance	$ 773,327,000	$ 761,067,000
Foreign currency translation adjustment	9,425,000	12,260,000
Ending Balance	782,752,000	773,327,000
Goodwill, Impaired, Accumulated Impairment Loss	0
Software
Goodwill [Roll Forward]
Beginning Balance	626,679,000	614,419,000
Foreign currency translation adjustment	9,425,000	12,260,000
Ending Balance	636,104,000	626,679,000
Scores
Goodwill [Roll Forward]
Beginning Balance	146,648,000	146,648,000
Foreign currency translation adjustment	0	0
Ending Balance	$ 146,648,000	$ 146,648,000