Allowance for Credit Losses - Credit Rating and Year of Origination (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Term Loans Amortized Cost Basis by Origination Year
Loans, gross	$ 1,909,409	$ 1,742,139
Consumer finance
Term Loans Amortized Cost Basis by Origination Year
2024	123,191	144,649
2023	118,364	179,264
2022	137,421	87,943
2021	63,406	32,238
2020	22,337	15,919
Prior	12,581	8,497
Loans, gross	477,300	468,510
Consumer finance \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	28,177	22,397
2023	17,804	27,395
2022	22,000	14,148
2021	11,193	10,964
2020	8,827	2,795
Prior	4,128	2,460
Loans, gross	92,129	80,159
Consumer finance \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	37,079	42,622
2023	35,036	50,930
2022	39,713	17,132
2021	12,217	4,722
2020	3,156	1,500
Prior	1,198	778
Loans, gross	128,399	117,684
Consumer finance \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024	34,183	44,492
2023	37,148	55,189
2022	41,728	26,682
2021	19,164	6,216
2020	3,906	3,984
Prior	2,309	1,507
Loans, gross	138,438	138,070
Consumer finance \| Fair
Term Loans Amortized Cost Basis by Origination Year
2024	19,812	28,779
2023	23,501	36,794
2022	27,507	22,266
2021	15,261	7,014
2020	4,392	4,808
Prior	2,988	1,908
Loans, gross	93,461	101,569
Consumer finance \| Marginal
Term Loans Amortized Cost Basis by Origination Year
2024	3,940	6,359
2023	4,875	8,956
2022	6,473	7,715
2021	5,571	3,322
2020	2,056	2,832
Prior	1,958	1,844
Loans, gross	24,873	31,028
Consumer finance \| Automobiles
Term Loans Amortized Cost Basis by Origination Year
2024	110,079	129,484
2023	105,081	155,913
2022	116,963	76,447
2021	53,579	20,872
2020	12,824	12,991
Prior	7,859	5,569
Loans, gross	406,385	401,276
Consumer finance \| Automobiles \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	19,654	14,916
2023	11,317	12,395
2022	8,863	4,291
2021	2,796	1,012
2020	550	277
Prior	125	22
Loans, gross	43,305	32,913
Consumer finance \| Automobiles \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	32,490	35,203
2023	28,443	42,800
2022	32,578	15,530
2021	10,822	3,338
2020	1,948	1,090
Prior	514	325
Loans, gross	106,795	98,286
Consumer finance \| Automobiles \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024	34,183	44,227
2023	36,945	54,968
2022	41,542	26,645
2021	19,129	6,186
2020	3,878	3,984
Prior	2,274	1,470
Loans, gross	137,951	137,480
Consumer finance \| Automobiles \| Fair
Term Loans Amortized Cost Basis by Origination Year
2024	19,812	28,779
2023	23,501	36,794
2022	27,507	22,266
2021	15,261	7,014
2020	4,392	4,808
Prior	2,988	1,908
Loans, gross	93,461	101,569
Consumer finance \| Automobiles \| Marginal
Term Loans Amortized Cost Basis by Origination Year
2024	3,940	6,359
2023	4,875	8,956
2022	6,473	7,715
2021	5,571	3,322
2020	2,056	2,832
Prior	1,958	1,844
Loans, gross	24,873	31,028
Consumer finance \| Marine and recreational vehicles
Term Loans Amortized Cost Basis by Origination Year
2024	13,112	15,165
2023	13,283	23,351
2022	20,458	11,496
2021	9,827	11,366
2020	9,513	2,928
Prior	4,722	2,928
Loans, gross	70,915	67,234
Consumer finance \| Marine and recreational vehicles \| Very good
Term Loans Amortized Cost Basis by Origination Year
2024	8,523	7,481
2023	6,487	15,000
2022	13,137	9,857
2021	8,397	9,952
2020	8,277	2,518
Prior	4,003	2,438
Loans, gross	48,824	47,246
Consumer finance \| Marine and recreational vehicles \| Good
Term Loans Amortized Cost Basis by Origination Year
2024	4,589	7,419
2023	6,593	8,130
2022	7,135	1,602
2021	1,395	1,384
2020	1,208	410
Prior	684	453
Loans, gross	21,604	19,398
Consumer finance \| Marine and recreational vehicles \| Fairly good
Term Loans Amortized Cost Basis by Origination Year
2024		265
2023	203	221
2022	186	37
2021	35	30
2020	28
Prior	35	37
Loans, gross	$ 487	$ 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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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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