Loans and Allowance for Credit Losses - Breakdown of Consumer Loan Portfolio by Segment and Type of Loan (Details)	6 Months Ended	9 Months Ended
Jun. 30, 2026 USD ($) loan	Sep. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) loan
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 4,215,122,000		$ 3,756,829,000
CCBX
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	2,226,296,000		1,808,094,000
Community Bank
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	1,988,826,000		1,948,735,000
Consumer and other loans:
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 1,682,710,000		$ 1,328,461,000
% of Total Outstanding Balance Consumer Loans	100.00%		100.00%
Average Loan Balance	$ 500	$ 809
Number of Loans \| loan	3,580,680		1,642,431
Consumer and other loans: \| CCBX
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 918,779,000		$ 691,708,000
Consumer and other loans: \| CCBX \| Installment Loans - Cash Secured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 216,766,000		$ 162,072,000
% of Total Outstanding Balance Consumer Loans	12.90%		12.20%
Consumer and other loans: \| CCBX \| Installment Loans - Unsecured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 521,555,000		$ 502,767,000
% of Total Outstanding Balance Consumer Loans	31.00%		37.80%
Consumer and other loans: \| CCBX \| Installment Loans - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 738,321,000		$ 664,839,000
% of Total Outstanding Balance Consumer Loans	43.90%		50.00%
Average Loan Balance	$ 400	800
Number of Loans \| loan	1,851,498		864,638
Consumer and other loans: \| CCBX \| Credit Cards - Cash Secured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 54,000		$ 56,000
% of Total Outstanding Balance Consumer Loans	0.00%		0.00%
Consumer and other loans: \| CCBX \| Credit Cards - Unsecured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 753,117,000		$ 622,625,000
% of Total Outstanding Balance Consumer Loans	44.80%		46.90%
Consumer and other loans: \| CCBX \| Credit Cards - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 753,171,000		$ 622,681,000
% of Total Outstanding Balance Consumer Loans	44.80%		46.90%
Average Loan Balance	$ 1,500	1,400
Number of Loans \| loan	500,348		435,236
Consumer and other loans: \| CCBX \| Lines Of Credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 144,947,000		$ 10,027,000
% of Total Outstanding Balance Consumer Loans	8.60%		0.80%
Average Loan Balance	$ 200	100
Number of Loans \| loan	943,772		89,736
Consumer and other loans: \| CCBX \| Consumer, Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 35,511,000		$ 16,842,000
% of Total Outstanding Balance Consumer Loans	2.10%		1.30%
Average Loan Balance	$ 100	100
Number of Loans \| loan	284,612		252,381
Consumer and other loans: \| Community Bank
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 10,760,000		$ 14,072,000
Consumer and other loans: \| Community Bank \| Installment Loans - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 681,000		$ 3,010,000
% of Total Outstanding Balance Consumer Loans	0.00%		0.20%
Average Loan Balance	$ 28,400	111,500
Number of Loans \| loan	24		27
Consumer and other loans: \| Community Bank \| Lines Of Credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 210,000		$ 140,000
% of Total Outstanding Balance Consumer Loans	0.00%		0.00%
Average Loan Balance	$ 6,800	4,500
Number of Loans \| loan	31		31
Consumer and other loans: \| Community Bank \| Consumer, Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 9,869,000		$ 10,922,000
% of Total Outstanding Balance Consumer Loans	0.60%		0.80%
Average Loan Balance	$ 25,000.0	$ 28,600
Number of Loans \| loan	395		382

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Percentage, before allowance for credit loss, of financing receivable to total financing receivable.

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

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Average amount outstanding, before allowance for credit loss, of financing receivables.

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