Goodwill - Schedule of Changes to Goodwill (Details) $ in Thousands	6 Months Ended
	Mar. 31, 2026 USD ($)
Goodwill [Roll Forward]
Balance at September 30, 2025	$ 783,340
Foreign currency translation adjustment	(1,950)
Balance at March 31, 2026	781,390
Scores
Goodwill [Roll Forward]
Balance at September 30, 2025	146,648
Foreign currency translation adjustment	0
Balance at March 31, 2026	146,648
Software
Goodwill [Roll Forward]
Balance at September 30, 2025	636,692
Foreign currency translation adjustment	(1,950)
Balance at March 31, 2026	$ 634,742