v3.22.0.1

Retirement Plans (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Defined Benefit Plan, Plan Assets, Allocation [Line Items] |  |
Company's contribution, percent of eligible compensation | 3.00% |
Company's contribution to the plan | $ 398 | $ 879
Total vesting percentage | 100.00% |
Service period | 10 years |
Continuous employment period | 10 years |
Age of participant attaining separation under the LTIP | 67 years |
Chief Executive Officer |  |
Defined Benefit Plan, Plan Assets, Allocation [Line Items] |  |
Defined contribution plan earn an annual contribution percent | 20.00% |
Executive Management |  |
Defined Benefit Plan, Plan Assets, Allocation [Line Items] |  |
Defined contribution plan earn an annual contribution percent | 15.00% |

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- Definition Long-Term Incentive Plan, Continuous Employment Period + References No definition available. + Details
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Namespace Prefix: | cbnk_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Long-Term Incentive Plan, Separation, Age Of Participant + References No definition available. + Details
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Namespace Prefix: | cbnk_
Data Type: | xbrli:durationItemType
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- Definition Long-Term Incentive Plan, Service Period + References No definition available. + Details
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Namespace Prefix: | cbnk_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

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- Definition Long-Term Incentive Plan, Total Vesting Percentage + References No definition available. + Details
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Data Type: | dtr-types:percentItemType
Balance Type: | na
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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Data Type: | xbrli:stringItemType
Balance Type: | na
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- Definition Amount of discretionary contributions made by an employer to a defined contribution plan. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
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- Definition Percentage of employees' gross pay for which the employer contributes a matching contribution to a defined contribution plan. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

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- Definition Maximum percentage of employee gross pay the employee may contribute to a defined contribution plan. + References No definition available. + Details
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Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | duration

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- Details
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Namespace Prefix: |
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |