cm:Level2TextBlock: us-gaap:PensionAndOtherPostretirementPlansPensionsPolicy
| Pension and Other Postretirement Plans, Pensions, Policy [Policy Text Block] |
| us-gaap:PensionAndOtherPostretirementPlansPensionsPolicy |
| Disclosure of accounting policy for pension plans. This accounting policy may address (1) the types of plans sponsored by the entity (2) groups that participate in (or are covered by) each plan (3) how plan assets, liabilities and expenses are measured, including the use of any actuaries and (4) significant assumptions used by the entity to value plan assets and liabilities and how such assumptions are derived. |
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| us-gaap:PensionAndOtherPostretirementPlansPensionsPolicy |