cm:Concept: us-gaap:DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1
Defined Benefit Plan, Effect of One Percentage Point Decrease on Service and Interest Cost Components |
us-gaap:DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 |
Amount of decrease in service and interest cost components of net periodic postretirement benefit cost from one-percentage-point decrease in assumed health care cost trend rate. |
cm:Concept |
Monetary (xbrli:monetaryItemType) |
For Period (duration) |
Credit |
false |
us-gaap:DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1 |