Finance Receivables, Credit Quality Information, and Allowance for Credit Losses - Summary of Modification Made to Borrowers Experiencing Financial Difficulty (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 9,427	$ 9,428	$ 18,909	$ 19,266
% of Net finance receivables	0.40%	0.50%	0.90%	1.00%
Interest Rate Reduction [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 6,832	$ 5,875	$ 14,353	$ 12,670
% of Net finance receivables	0.30%	0.30%	0.70%	0.60%
Interest Rate Reduction and Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 1,671	$ 2,256	$ 3,384	$ 4,979
% of Net finance receivables	0.10%	0.10%	0.20%	0.30%
Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 793	$ 1,049	$ 888	$ 1,195
% of Net finance receivables		0.10%		0.10%
Principal Forgiveness, Interest Rate Reduction, & Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	131	$ 248	284	$ 422
Large Loans [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 7,665	$ 7,481	$ 14,901	$ 15,061
% of Net finance receivables	0.50%	0.50%	0.90%	1.10%
Large Loans [Member] \| Interest Rate Reduction [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 5,446	$ 4,484	$ 11,123	$ 9,536
% of Net finance receivables	0.40%	0.30%	0.70%	0.70%
Large Loans [Member] \| Interest Rate Reduction and Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 1,412	$ 1,831	$ 2,780	$ 4,111
% of Net finance receivables	0.10%	0.10%	0.20%	0.30%
Large Loans [Member] \| Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 682	$ 924	$ 729	$ 1,008
% of Net finance receivables		0.10%		0.10%
Large Loans [Member] \| Principal Forgiveness, Interest Rate Reduction, & Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	125	$ 242	269	$ 406
Small Loans [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 1,762	$ 1,947	$ 4,008	$ 4,205
% of Net finance receivables	0.40%	0.40%	0.80%	0.80%
Small Loans [Member] \| Interest Rate Reduction [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 1,386	$ 1,391	$ 3,230	$ 3,134
% of Net finance receivables	0.30%	0.30%	0.70%	0.60%
Small Loans [Member] \| Interest Rate Reduction and Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 259	$ 425	$ 604	$ 868
% of Net finance receivables	0.10%	0.10%	0.10%	0.20%
Small Loans [Member] \| Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 111	$ 125	$ 159	$ 187
Small Loans [Member] \| Principal Forgiveness, Interest Rate Reduction, & Term Extension [Member]
Financing Receivable, Modified [Line Items]
Amortized cost basis	$ 6	$ 6	$ 15	$ 16