cm:Level2TextBlock: us-gaap:RepurchaseAndResaleAgreementsPolicy
| Repurchase and Resale Agreements Policy [Policy Text Block] |
| us-gaap:RepurchaseAndResaleAgreementsPolicy |
| Disclosure of accounting policy for repurchase and resale agreements. This disclosure may address (a) the reasons for entering into repurchase and resale agreements, (b) how securities transferred under such agreements are classified in the entity's financial statements, (c) whether multiple agreements with the same counterparty are offset (d) the entity's accounting policy for requiring collateral or other security for such transactions, and (e) how the entity ensures that the market value of the underlying assets remains sufficient to protect the entity in the event of default by the counterparty. |
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| us-gaap:RepurchaseAndResaleAgreementsPolicy |