Securitizations and Variable Interest Entities - Summary of Personal Whole Loan Securitizations and Sales (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Unconsolidated Trusts
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Principal derecognized from loans securitized or sold	$ 0	$ 255,203
Net gains recognized from loans securitized or sold	0	(20)
Fair value of asset-backed senior and subordinated securities, and CLUB Certificate asset-backed securities retained upon settlement	0	12,707
Proceeds from issuance of notes and certificates from Structured Program transactions	0	237,764
Cash proceeds from servicing and other administrative fees on loans securitized or sold	9,141	17,684
Cash proceeds for interest received on senior securities and subordinated securities	2,978	4,559
Unconsolidated Certificate Program Trusts
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Principal derecognized from loans securitized or sold	0	971,738
Net gains recognized from loans securitized or sold	0	7,897
Fair value of asset-backed senior and subordinated securities, and CLUB Certificate asset-backed securities retained upon settlement	0	35,836
Proceeds from issuance of notes and certificates from Structured Program transactions	0	598,694
Cash proceeds from servicing and other administrative fees on loans securitized or sold	14,445	26,822
Cash proceeds for interest received on senior securities and subordinated securities	$ 6,158	8,251
Structured Program Transactions \| Senior securities
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Transferor's interests retained in transferred financial assets, fair value		26,300
Structured Program Transactions \| CLUB Certificate asset-backed securities
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Transferor's interests retained in transferred financial assets, fair value		18,300
Structured Program Transactions \| Subordinated securities
Fair Value Assumption, Date of Securitization or Asset-backed Financing Arrangement, Transferor's Continuing Involvement, Servicing Assets or Liabilities [Line Items]
Transferor's interests retained in transferred financial assets, fair value		$ 4,000

Debt Securities, Available-for-sale, Retained upon Settlement

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Principal Amount Outstanding on Loans Securitized or Asset-backed Financing Arrangement, Derecognized during Period

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Proceeds from Servicing Rights Fees on Securitizations

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Transferor's Interests Retained In Transferred Financial Assets, Fair Value

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Cash received for dividends and interest on the entity's equity and debt investments during the current period.

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The cash inflow from the securitization of receivables for loans to consumers. Securitization is the structured process whereby interests in loans and other receivables are packaged, underwritten, and sold in the form of asset-backed securities.

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