v3.25.3

Portfolio Loans Receivable and Allowance for Credit Losses - Schedule of Credit Losses for Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	$ 47,447	$ 30,832	$ 48,652	$ 28,610
Provision for (release of) credit losses	4,650	3,748	10,977	9,892
Balance at end of period	53,045	31,925	53,045	31,925
Unfunded Lines of Credit
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	1,191	1,052	1,191	806
Provision for (release of) credit losses	217	17	217	263
Balance at end of period	1,408	1,069	1,408	1,069
Mortgage Loans Sold
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of period	2,294	912	2,260	985
Provision for (release of) credit losses	19	20	53	(53)
Balance at end of period	$ 2,313	$ 932	$ 2,313	$ 932

X

- Definition

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cbnk_MortgageLoansSoldMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: