Disaggregation of Revenue (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2024 USD ($) Segment customer	Dec. 31, 2023 USD ($) Segment	Sep. 30, 2024 customer
Disaggregation of Revenue [Line Items]
Total revenues	$ 439,968	$ 382,059
Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
Revenue from Contract with Customer Benchmark [Member] | Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
Revenue from Contract with Customer Benchmark [Member] | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Revenue, Number of Customers | Segment	(3)	(3)
Revenue from Contract with Customer Benchmark [Member] | Customer Concentration Risk | TransUnion, Equifax and Experian customers
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	44.00%	39.00%
Accounts Receivable | Customer Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Receivables, Number of Customers | customer	1		1
On-premises and SaaS software
Disaggregation of Revenue [Line Items]
Total revenues	$ 186,011	$ 168,668
On-premises and SaaS software | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
On-premises and SaaS software | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk | Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	12.00%	8.00%
On-premises and SaaS software | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk | Transferred over Time
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	88.00%	92.00%
On-Premises | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	45.00%	43.00%
SaaS Products | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	55.00%	57.00%
Platform software | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	29.00%	27.00%
Non-platform software | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	71.00%	73.00%
Americas
Disaggregation of Revenue [Line Items]
Total revenues	$ 379,875	$ 318,510
Americas | Revenue from Contract with Customer Benchmark [Member] | Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	87.00%	83.00%
EMEA
Disaggregation of Revenue [Line Items]
Total revenues	$ 36,359	$ 36,368
EMEA | Revenue from Contract with Customer Benchmark [Member] | Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	8.00%	10.00%
Asia Pacific
Disaggregation of Revenue [Line Items]
Total revenues	$ 23,734	$ 27,181
Asia Pacific | Revenue from Contract with Customer Benchmark [Member] | Geographic Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	5.00%	7.00%
Scores
Disaggregation of Revenue [Line Items]
Total revenues	$ 235,675	$ 192,112
Scores | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	100.00%	100.00%
Scores | Business to business Scores
Disaggregation of Revenue [Line Items]
Total revenues	$ 182,391	$ 140,442
Scores | Business to business Scores | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	77.00%	73.00%
Scores | Business to consumer Scores
Disaggregation of Revenue [Line Items]
Total revenues	$ 53,284	$ 51,670
Scores | Business to consumer Scores | Revenue from Contract with Customer Benchmark [Member] | Product Concentration Risk
Disaggregation of Revenue [Line Items]
Concentration Risk, Percentage	23.00%	27.00%
Scores | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	$ 235,675	$ 192,112
Scores | Operating Segments | On-premises and SaaS software
Disaggregation of Revenue [Line Items]
Total revenues	0	0
Scores | Americas
Disaggregation of Revenue [Line Items]
Total revenues	232,966	184,948
Scores | EMEA
Disaggregation of Revenue [Line Items]
Total revenues	1,877	1,308
Scores | Asia Pacific
Disaggregation of Revenue [Line Items]
Total revenues	832	5,856
Software
Disaggregation of Revenue [Line Items]
Total revenues	204,293	189,947
Software | On-premises and SaaS software
Disaggregation of Revenue [Line Items]
Total revenues	186,011	168,668
Software | On-premises and SaaS software | Transferred at Point in Time
Disaggregation of Revenue [Line Items]
Total revenues	22,808	13,782
Software | On-premises and SaaS software | Transferred over Time
Disaggregation of Revenue [Line Items]
Total revenues	163,203	154,886
Software | On-Premises
Disaggregation of Revenue [Line Items]
Total revenues	82,835	72,472
Software | SaaS Products
Disaggregation of Revenue [Line Items]
Total revenues	103,176	96,196
Software | Platform software
Disaggregation of Revenue [Line Items]
Total revenues	53,822	45,173
Software | Non-platform software
Disaggregation of Revenue [Line Items]
Total revenues	132,189	123,495
Software | Operating Segments
Disaggregation of Revenue [Line Items]
Total revenues	204,293	189,947
Software | Operating Segments | On-premises and SaaS software
Disaggregation of Revenue [Line Items]
Total revenues	186,011	168,668
Software | Americas
Disaggregation of Revenue [Line Items]
Total revenues	146,909	133,562
Software | EMEA
Disaggregation of Revenue [Line Items]
Total revenues	34,482	35,060
Software | Asia Pacific
Disaggregation of Revenue [Line Items]
Total revenues	$ 22,902	$ 21,325