| **Accounting Policies Pending Accounting Updates (Policies)** | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |
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| **Accounting Policies [Abstract]**                            |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| Adopted Accounting Updates and Pending Accounting Updates     | Pending Accounting UpdatesASU 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration ContractsIn August 2018, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) 2018-12, Financial Services - Insurance (Topic 944): Targeted Improvements to the Accounting for Long-Duration Contracts. ASU 2018-12 requires changes to the measurement and disclosure of long-duration insurance contracts. In November 2020, the FASB issued an ASU that delayed the effective date of ASU 2018-12 to interim and annual reporting periods beginning after December 15, 2022. We plan to adopt these ASUs on a modified retrospective basis on January 1, 2023.Related to the company's term and whole life products included in life policy and investment contract reserves, the new guidance requires that cash flow assumptions be reviewed at least annually to determine any necessary updates. Additionally, the discount rate assumption is required to be updated quarterly based on upper-medium grade fixed-income instrument yields (market value discount rates). The life policy and investment contract reserves balance is adjusted through insurance losses and contract holders' benefits for cash flow assumption updates and through accumulated other comprehensive income (AOCI) for discount rate updates.These ASUs also amend the previous guidance related to life deferred policy acquisition costs by requiring amortization of those costs on a constant level basis for a group of contracts that approximates straight-line and the removal of shadow deferred policy acquisition costs for universal life and deferred annuity products. These ASUs also require entities to provide additional disclosures including disaggregated rollforwards of the life policy and investment contract reserves, separate account liabilities and life deferred policy acquisition costs. Based on current conditions, management estimates at September 30, 2022, that adoption would not have a material impact and would have resulted in an after-tax increase to shareholders' equity of approximately $50 million. The ultimate impact of adoption of these ASUs will be affected by the market value discount rates and other assumptions determined at the January 1, 2023, adoption date and could be material. The process of addressing necessary remaining implementation-related items, including modifications to reporting and analysis capabilities as well as actuarial systems and associated data processes is substantially complete. |

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| - Definition
Disclosure of accounting policy pertaining to new accounting pronouncements that may impact the entity's financial reporting. Includes, but is not limited to, quantification of the expected or actual impact.
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