Allowance for Credit Losses - Credit Rating and Year of Origination (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Term Loans Amortized Cost Basis by Origination Year
Loans, gross	$ 1,742,139	$ 1,635,718
Consumer finance
Term Loans Amortized Cost Basis by Origination Year
2023	144,649
2022	179,264
2021	87,943
2020	32,238
2019	15,919
Prior	8,497
Loans, gross	468,510
Consumer finance | Very good
Term Loans Amortized Cost Basis by Origination Year
2023	22,397
2022	27,395
2021	14,148
2020	10,964
2019	2,795
Prior	2,460
Loans, gross	80,159
Consumer finance | Good
Term Loans Amortized Cost Basis by Origination Year
2023	42,622
2022	50,930
2021	17,132
2020	4,722
2019	1,500
Prior	778
Loans, gross	117,684
Consumer finance | Fairly good
Term Loans Amortized Cost Basis by Origination Year
2023	44,492
2022	55,189
2021	26,682
2020	6,216
2019	3,984
Prior	1,507
Loans, gross	138,070
Consumer finance | Fair
Term Loans Amortized Cost Basis by Origination Year
2023	28,779
2022	36,794
2021	22,266
2020	7,014
2019	4,808
Prior	1,908
Loans, gross	101,569
Consumer finance | Marginal
Term Loans Amortized Cost Basis by Origination Year
2023	6,359
2022	8,956
2021	7,715
2020	3,322
2019	2,832
Prior	1,844
Loans, gross	31,028
Consumer finance | Automobiles
Term Loans Amortized Cost Basis by Origination Year
2023	129,484
2022	155,913
2021	76,447
2020	20,872
2019	12,991
Prior	5,569
Loans, gross	401,276	411,112
Consumer finance | Automobiles | Very good
Term Loans Amortized Cost Basis by Origination Year
2023	14,916
2022	12,395
2021	4,291
2020	1,012
2019	277
Prior	22
Loans, gross	32,913
Consumer finance | Automobiles | Good
Term Loans Amortized Cost Basis by Origination Year
2023	35,203
2022	42,800
2021	15,530
2020	3,338
2019	1,090
Prior	325
Loans, gross	98,286
Consumer finance | Automobiles | Fairly good
Term Loans Amortized Cost Basis by Origination Year
2023	44,227
2022	54,968
2021	26,645
2020	6,186
2019	3,984
Prior	1,470
Loans, gross	137,480
Consumer finance | Automobiles | Fair
Term Loans Amortized Cost Basis by Origination Year
2023	28,779
2022	36,794
2021	22,266
2020	7,014
2019	4,808
Prior	1,908
Loans, gross	101,569
Consumer finance | Automobiles | Marginal
Term Loans Amortized Cost Basis by Origination Year
2023	6,359
2022	8,956
2021	7,715
2020	3,322
2019	2,832
Prior	1,844
Loans, gross	31,028
Consumer finance | Marine and recreational vehicles
Term Loans Amortized Cost Basis by Origination Year
2023	15,165
2022	23,351
2021	11,496
2020	11,366
2019	2,928
Prior	2,928
Loans, gross	67,234	$ 63,445
Consumer finance | Marine and recreational vehicles | Very good
Term Loans Amortized Cost Basis by Origination Year
2023	7,481
2022	15,000
2021	9,857
2020	9,952
2019	2,518
Prior	2,438
Loans, gross	47,246
Consumer finance | Marine and recreational vehicles | Good
Term Loans Amortized Cost Basis by Origination Year
2023	7,419
2022	8,130
2021	1,602
2020	1,384
2019	410
Prior	453
Loans, gross	19,398
Consumer finance | Marine and recreational vehicles | Fairly good
Term Loans Amortized Cost Basis by Origination Year
2023	265
2022	221
2021	37
2020	30
Prior	37
Loans, gross	$ 590