cm:Member: us-gaap:EffectOfRetrospectiveApplicationOfAccountingStandardsUpdate201812Member
| Effect of Retrospective Application of Accounting Standards Update 2018-12 [Member] |
| us-gaap:EffectOfRetrospectiveApplicationOfAccountingStandardsUpdate201812Member |
| Effect of retrospective application of Accounting Standards Update 2018-12 Financial Services-Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts. |
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| us-gaap:EffectOfRetrospectiveApplicationOfAccountingStandardsUpdate201812Member |