cm:Concept: us-gaap:ClosedBlockLiabilitiesPolicyholderDividendObligation
| Closed Block Dividend Obligation |
| us-gaap:ClosedBlockLiabilitiesPolicyholderDividendObligation |
| The liability as of the balance sheet date for the excess of the cumulative actual closed block earnings over the cumulative expected (actuarially determined) closed block earnings (each) for the period from the actuarial calculation date to the date of measurement. The excess will result in future dividends to closed block policyholders, unless offset by less favorable than expected future performance of the closed block. The policyholder dividend obligation, which may not have a negative balance, recognizes that a portion of earnings in certain cases will not inure to the stockholders of the insurance entity. |
| cm:Concept |
| Monetary (xbrli:monetaryItemType) |
| As Of (instant) |
| Credit |
| false |
| us-gaap:ClosedBlockLiabilitiesPolicyholderDividendObligation |