Fair Value of Financial Instruments - Carrying Values and Estimated Fair Values of Assets and Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Debt Instrument, Fair Value Disclosure	$ 10,975,688	$ 9,151,263
Carrying Value
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Guarantee obligation	4,649	5,781
Debt Instrument, Fair Value Disclosure	10,975,688	9,151,263
ABS issued, net, At amortized cost	579,862	660,617
Total ABS issued, net	11,555,550	9,811,880
Debt obligation facilities and other financing	2,670,129	2,596,582
Convertible notes, net	466,110	503,728
Trust preferred securities and subordinated notes, net	138,836	138,813
Total debt obligations, net	3,414,626	3,239,123
Carrying Value \| Senior Notes
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Senior Notes	139,551	0
Estimated Fair Value
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Guarantee obligation	3,385	3,772
Debt Instrument, Fair Value Disclosure	10,975,688	9,151,263
ABS issued, net, At amortized cost	584,155	637,816
Total ABS issued, net	11,559,843	9,789,079
Debt obligation facilities and other financing	2,669,070	2,591,931
Convertible notes, net	469,876	488,341
Trust preferred securities and subordinated notes, net	93,465	92,070
Total debt obligations, net	3,376,871	3,172,342
Estimated Fair Value \| Senior Notes
Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract]
Senior Notes	$ 144,460	$ 0

Debt Instrument, Asset Backed Securities Issued, Amortized Cost

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- Definition

Trust Preferred Securities And Subordinated Notes, Net, Fair Value Disclosure

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No definition available.

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- Definition

Investments in notes or bonds that are collateralized by a specific group of underlying assets owned by the issuer of the notes or bonds which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

+ References

No definition available.

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Fair value portion of borrowing which can be exchanged for a specified number of another security at the option of the issuer or the holder, for example, but not limited to, the entity's common stock.

+ References

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Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

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- References

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

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- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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