v3.22.2.2

Portfolio Loans Receivable - Activity in Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	$ 26,419	$ 24,079	$ 25,181	$ 23,434
Provision for (reversal of) off balance sheet credit commitments	1,260	975	4,247	2,259
Ending Balance	26,091	24,753	26,091	24,753
Off Balance Sheet Reserve
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,631	1,745	1,736	1,775
Provision for (reversal of) off balance sheet credit commitments	51	(9)	(54)	(39)
Ending Balance	1,682	1,736	1,682	1,736
Mortgage Loan Put-back Reserve
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning Balance	1,166	1,369	1,164	1,160
Provision for (reversal of) off balance sheet credit commitments	4	70	6	279
Ending Balance	$ 1,170	$ 1,439	$ 1,170	$ 1,439

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossExcludingAccruedInterest
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

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesRollForward
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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

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

X

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_UnfundedLoanCommitmentMember
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: