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

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

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- 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

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- 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

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- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_UnfundedLoanCommitmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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