cm:Level2TextBlock: us-gaap:CreditCardOriginationCostsPolicyTextBlock
| Credit Card Origination Costs, Policy [Policy Text Block] |
| us-gaap:CreditCardOriginationCostsPolicyTextBlock |
| Disclosure of accounting policy for identifying, measuring and capitalizing costs of obtaining or creating credit card accounts that are not private label credit cards. Includes, but is not limited to, the methodology of amortizing costs, contractual arrangements terms with third-party credit card intermediaries and classification of amounts due from those intermediaries. |
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| us-gaap:CreditCardOriginationCostsPolicyTextBlock |