Fair Value Measurement - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 06, 2024	Sep. 30, 2024	Sep. 24, 2021	Nov. 30, 2020
2025 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt stated percentage	0.00%					0.00%
2027 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt stated percentage	0.00%				0.00%
2030 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt stated percentage	0.00%		0.00%
Level 2 | Fair Value, Recurring | 2025 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities	$ 33,154	$ 32,567
Level 2 | Fair Value, Recurring | 2027 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities	114,751	112,738
Level 2 | Fair Value, Recurring | 2030 Notes, principal
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Liabilities	1,248,786	1,185,128
Level 2 | Fair Value, Recurring | Corporate bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents:	75,233	69,956
Short-term investments:	711,643	758,333
Funds held for customers:	498,565	486,362
Level 2 | Fair Value, Recurring | U.S. treasury securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments:	347,939	287,559
Funds held for customers:	892,084	868,705
Level 2 | Fair Value, Recurring | Asset-backed securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments:	130,297	118,236
Funds held for customers:	148,582	167,970
Level 2 | Fair Value, Recurring | Certificates of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents:	0			$ 2,216
Short-term investments:	25,460	15,982
Funds held for customers:	94,136	99,138
Level 2 | Fair Value, Recurring | Municipal bonds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Funds held for customers:	15,409	6,592
Money market funds | Level 1 | Fair Value, Recurring | Cash equivalents:
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Cash equivalents:	367,960	365,456
Money market funds | Level 1 | Fair Value, Recurring | Restricted cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Funds held for customers:	1,755,709	1,642,494
Corporate bonds | Level 2 | Fair Value, Recurring | Restricted cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Funds held for customers:	$ 0	$ 18,929