Revenue - Schedule of Subscription and Transaction Fees Disaggregated by Customer Category (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Mar. 31, 2026	Mar. 31, 2025	Mar. 31, 2026	Mar. 31, 2025
Disaggregation Of Revenue [Line Items]
Total revenue	$ 406,563	$ 358,217	$ 1,216,974	$ 1,079,221
Subscription and transaction fees
Disaggregation Of Revenue [Line Items]
Total revenue	371,134	320,298	1,104,267	954,857
Integrated platform
Disaggregation Of Revenue [Line Items]
Total revenue	350,450	301,683	1,038,679	897,271
BILL AP/AR
Disaggregation Of Revenue [Line Items]
Total revenue	183,223	163,775	547,689	492,905
BILL Spend and Expense
Disaggregation Of Revenue [Line Items]
Total revenue	167,227	137,908	490,990	404,366
Embedded Solutions and Other
Disaggregation Of Revenue [Line Items]
Total revenue	20,684	18,615	65,588	57,586
Interest on funds held for customers
Disaggregation Of Revenue [Line Items]
Total revenue	$ 35,429	$ 37,919	$ 112,707	$ 124,364