Loans Held for Investment and Allowance for Credit Losses - Additional Information (Details) $ in Millions	12 Months Ended
Jun. 30, 2026 USD ($) deferral	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Loans purchased	$ 40,200.0	$ 30,000.0	$ 21,500.0
Loans originated	$ 9,500.0	$ 6,300.0	$ 4,500.0
Period of suspended accrued interest past due	120 days
Financing receivable, modified, number of deferrals \| deferral	1
Financing receivable, modified, length of deferral term	1 month	1 month	1 month
Financing receivable, modified, length of remaining term, maximum	24 months
Financing receivable, excluding accrued interest, modified, subsequent default	$ 7.1	$ 6.5	$ 13.3
Maximum
Financing Receivable, Allowance for Credit Loss [Line Items]
Loan lending terms	60 months
Financing receivable, modified, length of deferral term	3 months
Financing receivable, modified, weighted average term increase from modification	12 months	12 months	12 months
Minimum
Financing Receivable, Allowance for Credit Loss [Line Items]
Financing receivable, modified, weighted average term increase from modification	1 month	1 month	1 month

Financing Receivable, Excluding Accrued Interest, Originated Loans

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- Definition

Financing Receivable, Loan Term

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Financing Receivable, Modified, Length Of Deferral Term

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Financing Receivable, Modified, Length Of Remaining Term, Maximum

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- Definition

Financing Receivable, Modified, Number Of Deferrals

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- Definition

Financing Receivable, Threshold Period Past Due, Suspended Accrued Interest

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from purchase of loan. Excludes financing receivable purchased with credit deterioration, loan acquired through business combination or acquisition, and net investment in lease.

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- Definition

Amortized cost excluding accrued interest, of financing receivable with payment default in current period and modified within previous 12 months preceding payment default for debtor experiencing financial difficulty.

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- Definition

Period of increase in weighted-average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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