The Company and Its Significant Accounting Policies - Segment Reporting (Narrative) (Details) $ in Millions	3 Months Ended	9 Months Ended
Mar. 31, 2026 USD ($)	Mar. 31, 2025 USD ($)	Mar. 31, 2026 USD ($) Segment	Mar. 31, 2025 USD ($)
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Number of operating segments \| Segment			1
External customer revenue, percentage	2.00%	2.00%	2.00%	2.00%
Sales and marketing
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Rewards and promotions expense	$ 85.3	$ 68.4	$ 253.6	$ 195.2
General and administrative
Organization Consolidation Basis Of Presentation Business Description And Accounting Policies [Line Items]
Rewards and promotions expense	$ 4.5	$ 5.1	$ 16.5	$ 13.3

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 49
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482785/280-10-55-49

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482810/280-10-50-18

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