Finance Receivables, Credit Quality Information, and Allowance for Credit Losses - Summary of Financing Receivable Credit Quality Indicators (Detail) - USD ($) $ in Thousands	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	$ 1,198,168	$ 1,497,721
2025	734,688	436,202
2024	192,305	143,973
2023	62,980	52,423
2022	19,065	9,079
Prior	2,719	801
Total Net Finance Receivables	2,209,925	2,140,199	$ 2,053,017
FICO Band 1 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	163,240	202,359
2025	93,658	49,218
2024	22,261	17,162
2023	7,913	5,301
2022	2,486	1,509
Prior	895	395
Total Net Finance Receivables	290,453	275,944
FICO Band 2 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	95,196	111,790
2025	50,943	27,587
2024	11,784	7,637
2023	3,108	2,148
2022	813	385
Prior	166	48
Total Net Finance Receivables	162,010	149,595
FICO Band 3 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	141,257	175,021
2025	80,969	44,967
2024	19,447	14,199
2023	6,328	5,495
2022	2,031	747
Prior	203	51
Total Net Finance Receivables	250,235	240,480
FICO Band 4 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	174,303	223,052
2025	106,040	62,956
2024	27,644	21,530
2023	9,508	8,664
2022	3,095	1,134
Prior	315	80
Total Net Finance Receivables	320,905	317,416
FICO Band 5 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	180,636	237,016
2025	117,113	75,137
2024	32,675	24,089
2023	10,780	10,086
2022	3,732	1,898
Prior	503	91
Total Net Finance Receivables	345,439	348,317
FICO Band 6 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	443,536	548,483
2025	285,965	176,337
2024	78,494	59,356
2023	25,343	20,729
2022	6,908	3,406
Prior	637	136
Total Net Finance Receivables	840,883	808,447
Large Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	906,795	1,061,776
2025	582,855	336,199
2024	169,219	133,686
2023	61,570	51,732
2022	18,898	8,995
Prior	2,676	783
Total Net Finance Receivables	1,742,013	1,593,171	1,512,140
Large Loans [Member] \| FICO Band 1 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	101,868	119,724
2025	66,407	36,692
2024	18,935	15,225
2023	7,430	5,034
2022	2,405	1,453
Prior	868	382
Total Net Finance Receivables	197,913	178,510
Large Loans [Member] \| FICO Band 2 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	68,401	75,189
2025	39,188	21,423
2024	10,288	6,854
2023	2,987	2,086
2022	801	383
Prior	166	48
Total Net Finance Receivables	121,831	105,983
Large Loans [Member] \| FICO Band 3 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	103,201	121,142
2025	64,214	35,473
2024	17,478	13,157
2023	6,156	5,398
2022	2,007	739
Prior	194	51
Total Net Finance Receivables	193,250	175,960
Large Loans [Member] \| FICO Band 4 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	134,074	160,692
2025	85,701	50,359
2024	25,042	20,102
2023	9,309	8,588
2022	3,078	1,130
Prior	313	77
Total Net Finance Receivables	257,517	240,948
Large Loans [Member] \| FICO Band 5 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	142,007	173,379
2025	94,337	58,320
2024	28,911	22,357
2023	10,606	9,995
2022	3,715	1,893
Prior	501	90
Total Net Finance Receivables	280,077	266,034
Large Loans [Member] \| FICO Band 6 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	357,244	411,650
2025	233,008	133,932
2024	68,565	55,991
2023	25,082	20,631
2022	6,892	3,397
Prior	634	135
Total Net Finance Receivables	691,425	625,736
Small Loans [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	291,373	435,945
2025	151,833	100,003
2024	23,086	10,287
2023	1,410	691
2022	167	84
Prior	43	18
Total Net Finance Receivables	467,912	547,028	$ 540,877
Small Loans [Member] \| FICO Band 1 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	61,372	82,635
2025	27,251	12,526
2024	3,326	1,937
2023	483	267
2022	81	56
Prior	27	13
Total Net Finance Receivables	92,540	97,434
Small Loans [Member] \| FICO Band 2 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	26,795	36,601
2025	11,755	6,164
2024	1,496	783
2023	121	62
2022	12	2
Prior	0	0
Total Net Finance Receivables	40,179	43,612
Small Loans [Member] \| FICO Band 3 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	38,056	53,879
2025	16,755	9,494
2024	1,969	1,042
2023	172	97
2022	24	8
Prior	9	0
Total Net Finance Receivables	56,985	64,520
Small Loans [Member] \| FICO Band 4 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	40,229	62,360
2025	20,339	12,597
2024	2,602	1,428
2023	199	76
2022	17	4
Prior	2	3
Total Net Finance Receivables	63,388	76,468
Small Loans [Member] \| FICO Band 5 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	38,629	63,637
2025	22,776	16,817
2024	3,764	1,732
2023	174	91
2022	17	5
Prior	2	1
Total Net Finance Receivables	65,362	82,283
Small Loans [Member] \| FICO Band 6 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
2026	86,292	136,833
2025	52,957	42,405
2024	9,929	3,365
2023	261	98
2022	16	9
Prior	3	1
Total Net Finance Receivables	$ 149,458	$ 182,711

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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