Asset-Backed Financing - Assets and Liabilities of Variable Interest Entities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Finance receivables
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	$ 2,690,174	$ 3,114,992
Transfers accounts for as secured borrowings, assets, allowance for loan losses, carrying amount	(144,550)	(158,462)
Finance receivables | Asset-backed securitizations | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	2,348,817	2,558,450
Transfers accounts for as secured borrowings, assets, allowance for loan losses, carrying amount	(126,882)	(130,774)
Finance receivables | Asset-backed U.S. commercial paper conduit facility | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	259,441	474,167
Transfers accounts for as secured borrowings, assets, allowance for loan losses, carrying amount	(14,001)	(24,236)
Finance receivables | Asset-backed Canadian commercial paper conduit facility | Unconsolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	81,916	82,375
Transfers accounts for as secured borrowings, assets, allowance for loan losses, carrying amount	(3,667)	(3,452)
Restricted cash
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	115,005	146,001
Restricted cash | Asset-backed securitizations | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	94,137	114,254
Restricted cash | Asset-backed U.S. commercial paper conduit facility | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	16,443	26,874
Restricted cash | Asset-backed Canadian commercial paper conduit facility | Unconsolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	4,425	4,873
Other assets
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	8,996	9,935
Other assets | Asset-backed securitizations | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	6,719	7,899
Other assets | Asset-backed U.S. commercial paper conduit facility | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	2,066	1,906
Other assets | Asset-backed Canadian commercial paper conduit facility | Unconsolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	211	130
Total assets
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	2,669,625	3,112,466
Total assets | Asset-backed securitizations | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	2,322,791	2,549,829
Total assets | Asset-backed U.S. commercial paper conduit facility | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	263,949	478,711
Total assets | Asset-backed Canadian commercial paper conduit facility | Unconsolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, assets, carrying amount	82,885	83,926
Asset-backed debt
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, liabilities, carrying amount	2,181,368	2,516,993
Asset-backed debt | Asset-backed securitizations | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, liabilities, carrying amount	1,877,368	2,019,414
Asset-backed debt | Asset-backed U.S. commercial paper conduit facility | Consolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, liabilities, carrying amount	233,258	425,794
Asset-backed debt | Asset-backed Canadian commercial paper conduit facility | Unconsolidated VIEs:
Assets and Associated Liabilities of Transfers Accounted for as Secured Borrowings [Line Items]
Transfers accounts for as secured borrowings, liabilities, carrying amount	$ 70,742	$ 71,785