Loans and Allowance for Credit Losses - Breakdown of Consumer Loan Portfolio by Segment and Type of Loan (Details)	3 Months Ended	6 Months Ended
Mar. 31, 2026 USD ($) loan	Jun. 30, 2025 USD ($)	Dec. 31, 2025 USD ($) loan
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 3,866,474,000		$ 3,756,829,000
CCBX
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	1,884,641,000		1,808,094,000
Community Bank
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	1,981,833,000		1,948,735,000
Consumer and other loans:
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 1,432,015,000		$ 1,328,461,000
% of Total Outstanding Balance Consumer Loans	100.00%		100.00%
Average Loan Balance	$ 700	$ 809
Number of Loans \| loan	2,085,173		1,642,431
Consumer and other loans: \| CCBX
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 726,943,000		$ 691,708,000
Consumer and other loans: \| CCBX \| Installment Loans - Cash Secured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 174,036,000		$ 162,072,000
% of Total Outstanding Balance Consumer Loans	12.20%		12.20%
Consumer and other loans: \| CCBX \| Installment Loans - Unsecured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 495,508,000		$ 502,767,000
% of Total Outstanding Balance Consumer Loans	34.60%		37.80%
Consumer and other loans: \| CCBX \| Installment Loans - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 669,544,000		$ 664,839,000
% of Total Outstanding Balance Consumer Loans	46.80%		50.00%
Average Loan Balance	$ 700	800
Number of Loans \| loan	1,026,896		864,638
Consumer and other loans: \| CCBX \| Credit Cards - Cash Secured
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 398,000		$ 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	$ 693,087,000		$ 622,625,000
% of Total Outstanding Balance Consumer Loans	48.40%		46.90%
Consumer and other loans: \| CCBX \| Credit Cards - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 693,485,000		$ 622,681,000
% of Total Outstanding Balance Consumer Loans	48.40%		46.90%
Average Loan Balance	$ 1,500	1,400
Number of Loans \| loan	456,317		435,236
Consumer and other loans: \| CCBX \| Lines Of Credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 29,956,000		$ 10,027,000
% of Total Outstanding Balance Consumer Loans	2.10%		0.80%
Average Loan Balance	$ 100	100
Number of Loans \| loan	303,549		89,736
Consumer and other loans: \| CCBX \| Consumer, Other
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 27,443,000		$ 16,842,000
% of Total Outstanding Balance Consumer Loans	1.90%		1.30%
Average Loan Balance	$ 100	100
Number of Loans \| loan	297,989		252,381
Consumer and other loans: \| Community Bank
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 11,587,000		$ 14,072,000
Consumer and other loans: \| Community Bank \| Installment Loans - Total
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 1,088,000		$ 3,010,000
% of Total Outstanding Balance Consumer Loans	0.10%		0.20%
Average Loan Balance	$ 43,500	111,500
Number of Loans \| loan	25		27
Consumer and other loans: \| Community Bank \| Lines Of Credit
Financing Receivable, Allowance for Credit Loss [Line Items]
Gross loans receivable	$ 163,000		$ 140,000
% of Total Outstanding Balance Consumer Loans	0.00%		0.00%
Average Loan Balance	$ 5,300	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	$ 10,336,000		$ 10,922,000
% of Total Outstanding Balance Consumer Loans	0.70%		0.80%
Average Loan Balance	$ 28,200	$ 28,600
Number of Loans \| loan	366		382

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Average amount outstanding, before allowance for credit loss, of financing receivables.

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