Fair Value of Financial Assets and Liabilities - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unpaid balance on loans sold with retained servicing rights	$ 21,900,000	$ 15,800,000	$ 10,200,000
Unpaid principal balance on serviced sold loans	10,000,000	7,800,000
Servicing income	173,123	120,602	95,483
Servicing assets	$ 821	906
Economic risk retention	5.00%
Senior Notes and Residual Trust Certificates
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value	$ 68,358	75,469	$ 51,670
Fair Value, Liability, Recurring Basis, Unobservable Input Reconciliation, Liability, Gain (Loss), Statement of Other Comprehensive Income or Comprehensive Income [Extensible Enumeration]	Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent
Residual interests in structured transactions
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value	$ 5,600	$ 2,300

Loans Sold, Continuing Involvement with Transferred Financial Assets, Principal Amount Outstanding

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- Definition

Variable Interest Entity, Not Primary Beneficiary, Required Economic Risk Retention

+ References

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- Definition

Principal amount of transferred financial assets in which the transferor has continuing involvement with the assets underlying the transaction. Continuing involvement includes, but is not limited to, servicing, recourse, and restrictions on transferor's interests in transferred financial assets.

+ References

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- Definition

Amount of contractually specified servicing fee, late fee, and ancillary fee recognized as income for servicing asset and servicing liability.

+ References

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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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Fair value of financial instrument classified as a liability measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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- Definition

Indicates line item in statement in which other comprehensive income (OCI) is reported that includes gain (loss) from liability measured at fair value using unobservable input (level 3).

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- Definition

Aggregate amount of servicing assets that are subsequently measured at fair value and servicing assets that are subsequently measured using the amortization method.

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