|**VIEs (Tables)**                                                 | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                
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|**Variable Interest Entity and Securitizations [Abstract]**       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Summary of Variable Interest Entities                             | The assets of consolidated VIEs presented based upon the legal transfer of the underlying assets in order to reflect legal ownership, of which certain of these assets can be used only to settle obligations of the consolidated VIEs and the liabilities of those entities for which creditors (or beneficial interest holders) do not have recourse to the Company's general credit, included the following at the dates indicated:(in thousands)September 30, 2022December 31, 2021AssetsRestricted cash$1,028,120$1,637,311LHFI27,270,02120,551,716Operating lease assets, net10,863,45914,668,336Various other assets710,642629,364Total Assets$39,872,242$37,486,727LiabilitiesNotes payable$32,384,196$29,199,966Various other liabilities126,54781,098Total Liabilities$32,510,743$29,281,064                                                                        
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|(in thousands)                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Assets                                                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Restricted cash                                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|LHFI                                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Operating lease assets, net                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Various other assets                                              |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Assets                                                      |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Liabilities                                                       |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Notes payable                                                     |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Various other liabilities                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total Liabilities                                                 |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Summary of Cash Flows Received                                    | A summary of the cash flows received from the consolidated Trusts for the respective periods is as follows for the periods indicated:Three-Month Period Ended September 30,Nine-Month Period Ended September 30,(in thousands)2022202120222021Assets securitized$9,376,437$7,095,782$18,033,866$18,457,441Net proceeds from new securitizations(1)$6,594,664$6,591,786$12,736,284$16,168,394Net proceeds from sale of retained bonds912,632—1,942,378195,967Cash received for servicing fees(2)229,978228,194691,407686,789Net distributions from Trusts(2)893,7561,391,9703,100,6544,435,605Total cash received from Trusts$8,631,030$8,211,950$18,470,723$21,486,755(1)  Includes additional advances on existing securitizations.(2)These amounts are not reflected in the SCF because the cash flows are between the VIEs and other entities included in theconsolidation.
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|(in thousands)                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Assets securitized                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|Net proceeds from new securitizations(1)                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Net proceeds from sale of retained bonds                          |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Cash received for servicing fees(2)                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|Net distributions from Trusts(2)                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total cash received from Trusts                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Summary of Off-balance Sheet Variable Interest Entities Portfolio | The Company was servicing gross RICs that have been sold in off-balance sheet securitizations and were subject to an optional clean-up call as follows at the dates indicated:(in thousands)September 30, 2022December 31, 2021Related party SPAIN securitizations$264,197$554,040Third-party SCART serviced securitizations1,226,6211,817,936Total serviced for other portfolio$1,490,818$2,371,976                                                                                                                                                                                                                                                                                                                                                                                                                                                                          
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|(in thousands)                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Related party SPAIN securitizations                               |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|Third-party SCART serviced securitizations                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|Total serviced for other portfolio                                |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Summary of Securitization Transactions                            | A summary of cash flows received from Trusts for the respective periods were as follows for the periods indicated:Three-Month Period Ended September 30,Nine-Month Period Ended September 30,(in thousands)2022202120222021Receivables securitized(1)———1,891,278Net proceeds from new securitizations———1,779,532Cash received for servicing fees5,0238,04116,06124,061Total cash received from Trusts$5,023$8,041$16,061$1,803,593(1) Represents the UPB  at the time of original securitization.                                                                                                                                                                                                                                                                                                                                                                           
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|(in thousands)                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Receivables securitized(1)                                        |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
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|Net proceeds from new securitizations                             |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Cash received for servicing fees                                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total cash received from Trusts                                   |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               

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