Revenue - Schedule of Subscription and Transaction Fees Disaggregated by Customer Category (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2025	Dec. 31, 2024
Disaggregation Of Revenue [Line Items]
Total revenue	$ 414,671	$ 362,554	$ 810,413	$ 721,004
Subscription and transaction fees
Disaggregation Of Revenue [Line Items]
Total revenue	375,128	319,616	733,134	634,559
Integrated platform
Disaggregation Of Revenue [Line Items]
Total revenue	352,346	300,695	688,230	595,556
BILL AP/AR
Disaggregation Of Revenue [Line Items]
Total revenue	185,870	166,842	364,467	329,098
BILL Spend and Expense
Disaggregation Of Revenue [Line Items]
Total revenue	166,476	133,853	323,763	266,458
Embedded and Other Solutions
Disaggregation Of Revenue [Line Items]
Total revenue	22,782	18,921	44,904	39,003
Interest on funds held for customers
Disaggregation Of Revenue [Line Items]
Total revenue	$ 39,543	$ 42,938	$ 77,279	$ 86,445