Allowance for Credit Losses - Credit Rating and Year of Origination (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Term Loans Amortized Cost Basis by Origination Year
Loans, gross	$ 1,920,398	$ 1,742,139	$ 1,635,718
Consumer finance
Term Loans Amortized Cost Basis by Origination Year
2024	147,822	144,649
2023	108,397	179,264
2022	124,597	87,943
2021	56,176	32,238
2020	19,700	15,919
Prior	10,101	8,497
Loans, gross	466,793	468,510
Consumer finance \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	30,285	22,397
2023	16,322	27,395
2022	20,641	14,148
2021	10,362	10,964
2020	8,353	2,795
Prior	3,831	2,460
Loans, gross	89,794	80,159
Consumer finance \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	44,811	42,622
2023	32,156	50,930
2022	36,287	17,132
2021	10,728	4,722
2020	2,752	1,500
Prior	959	778
Loans, gross	127,693	117,684
Consumer finance \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024	41,881	44,492
2023	34,258	55,189
2022	37,669	26,682
2021	16,970	6,216
2020	3,240	3,984
Prior	1,636	1,507
Loans, gross	135,654	138,070
Consumer finance \| Fair
Term Loans Amortized Cost Basis by Origination Year
2024	25,796	28,779
2023	21,278	36,794
2022	24,379	22,266
2021	13,260	7,014
2020	3,674	4,808
Prior	2,194	1,908
Loans, gross	90,581	101,569
Consumer finance \| Marginal
Term Loans Amortized Cost Basis by Origination Year
2024	5,049	6,359
2023	4,383	8,956
2022	5,621	7,715
2021	4,856	3,322
2020	1,681	2,832
Prior	1,481	1,844
Loans, gross	23,071	31,028
Consumer finance \| Automobiles
Term Loans Amortized Cost Basis by Origination Year
2024	135,183	129,484
2023	95,488	155,913
2022	104,912	76,447
2021	46,812	20,872
2020	10,568	12,991
Prior	5,688	5,569
Loans, gross	398,651	401,276
Consumer finance \| Automobiles \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	22,161	14,916
2023	10,039	12,395
2022	7,971	4,291
2021	2,359	1,012
2020	426	277
Prior	77	22
Loans, gross	43,033	32,913
Consumer finance \| Automobiles \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	40,296	35,203
2023	25,730	42,800
2022	29,455	15,530
2021	9,402	3,338
2020	1,574	1,090
Prior	334	325
Loans, gross	106,791	98,286
Consumer finance \| Automobiles \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024	41,881	44,227
2023	34,058	54,968
2022	37,486	26,645
2021	16,935	6,186
2020	3,213	3,984
Prior	1,602	1,470
Loans, gross	135,175	137,480
Consumer finance \| Automobiles \| Fair
Term Loans Amortized Cost Basis by Origination Year
2024	25,796	28,779
2023	21,278	36,794
2022	24,379	22,266
2021	13,260	7,014
2020	3,674	4,808
Prior	2,194	1,908
Loans, gross	90,581	101,569
Consumer finance \| Automobiles \| Marginal
Term Loans Amortized Cost Basis by Origination Year
2024	5,049	6,359
2023	4,383	8,956
2022	5,621	7,715
2021	4,856	3,322
2020	1,681	2,832
Prior	1,481	1,844
Loans, gross	23,071	31,028
Consumer finance \| Marine and recreational vehicles
Term Loans Amortized Cost Basis by Origination Year
2024	12,639	15,165
2023	12,909	23,351
2022	19,685	11,496
2021	9,364	11,366
2020	9,132	2,928
Prior	4,413	2,928
Loans, gross	68,142	67,234
Consumer finance \| Marine and recreational vehicles \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	8,124	7,481
2023	6,283	15,000
2022	12,670	9,857
2021	8,003	9,952
2020	7,927	2,518
Prior	3,754	2,438
Loans, gross	46,761	47,246
Consumer finance \| Marine and recreational vehicles \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	4,515	7,419
2023	6,426	8,130
2022	6,832	1,602
2021	1,326	1,384
2020	1,178	410
Prior	625	453
Loans, gross	20,902	19,398
Consumer finance \| Marine and recreational vehicles \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024		265
2023	200	221
2022	183	37
2021	35	30
2020	27
Prior	34	37
Loans, gross	$ 479	$ 590

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Section 50
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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