0000001 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - Consolidated Statement of Income (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - Consolidated Statement of Comprehensive Income (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - Consolidated Balance Sheet (Unaudited at March 31, 2026) link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - Consolidated Balance Sheet Parentheticals (Unaudited at March 31, 2026) link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - Consolidated Statement of Changes in Shareholders' Equity (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952156 - Statement - Consolidated Statement of Cash Flows (Unaudited) link:presentationLink link:calculationLink link:definitionLink 9952157 - Disclosure - Basis of Presentation and Accounting Policies link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Segment Information link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Investments link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Fair Value Measurements link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Allowance for Expected Credit Losses link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Goodwill and Other Intangible Assets link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Insurance Claim Reserves link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Common Share Repurchases link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Earnings per Share link:presentationLink link:calculationLink link:definitionLink 9952167 - Disclosure - Share-Based Incentive Compensation link:presentationLink link:calculationLink link:definitionLink 9952168 - Disclosure - Pension Plans, Retirement Benefits and Savings Plans link:presentationLink link:calculationLink link:definitionLink 9952169 - Disclosure - Leases link:presentationLink link:calculationLink link:definitionLink 9952170 - Disclosure - Contingencies, Commitments and Guarantees link:presentationLink link:calculationLink link:definitionLink 9952171 - Disclosure - Noncash Investing and Financing Activities link:presentationLink link:calculationLink link:definitionLink 9955511 - Disclosure - Basis of Presentation and Accounting Policies (Policies) link:presentationLink link:calculationLink link:definitionLink 9955512 - Disclosure - Basis of Presentation and Accounting Policies (Table) link:presentationLink link:calculationLink link:definitionLink 9955513 - Disclosure - Segment Information (Tables) link:presentationLink link:calculationLink link:definitionLink 9955514 - Disclosure - Investments (Tables) link:presentationLink link:calculationLink link:definitionLink 9955515 - Disclosure - Fair Value Measurements (Tables) link:presentationLink link:calculationLink link:definitionLink 9955516 - Disclosure - Allowance for Expected Credit Losses (Tables) link:presentationLink link:calculationLink link:definitionLink 9955517 - Disclosure - Goodwill and Other Intangible Assets (Tables) link:presentationLink link:calculationLink link:definitionLink 9955518 - Disclosure - Insurance Claim Reserves (Tables) link:presentationLink link:calculationLink link:definitionLink 9955519 - Disclosure - Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) (Tables) link:presentationLink link:calculationLink link:definitionLink 9955520 - Disclosure - Earnings per Share (Table) link:presentationLink link:calculationLink link:definitionLink 9955521 - Disclosure - Share-Based Incentive Compensation (Table) link:presentationLink link:calculationLink link:definitionLink 9955522 - Disclosure - Pension Plans, Retirement Benefits and Savings Plans (Table) link:presentationLink link:calculationLink link:definitionLink 9955523 - Disclosure - Leases (Table) link:presentationLink link:calculationLink link:definitionLink 9955524 - Disclosure - Basis of Presentation and Accounting Policies (Details) link:presentationLink link:calculationLink link:definitionLink 9955525 - Disclosure - Basis of Presentation and Accounting Policies (Details) - Held For Sale link:presentationLink link:calculationLink link:definitionLink 9955526 - Disclosure - Segment Information (Details) link:presentationLink link:calculationLink link:definitionLink 9955527 - Disclosure - Segment Information (Details) - Prior Year Development and Catastrophes link:presentationLink link:calculationLink link:definitionLink 9955528 - Disclosure - Segment Information (Details) - Amortization and Depreciation link:presentationLink link:calculationLink link:definitionLink 9955529 - Disclosure - Segment Information (Details) - Assets by Segment link:presentationLink link:calculationLink link:definitionLink 9955530 - Disclosure - Investments (Details) - Investment Information, Debt Securities link:presentationLink link:calculationLink link:definitionLink 9955531 - Disclosure - Investments (Details) - Investment Information, Equity Securities link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Investments (Details) - Investment Information, Losses link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Investments (Details) - Allowance for Expected Credit Losses link:presentationLink link:calculationLink link:definitionLink 9955534 - Disclosure - Investments (Details) - Other Investments link:presentationLink link:calculationLink link:definitionLink 9955535 - Disclosure - Fair Value Measurements (Details) link:presentationLink link:calculationLink link:definitionLink 9955536 - Disclosure - Fair Value Measurements (Details) - Fair Value Hierarchy link:presentationLink link:calculationLink link:definitionLink 9955537 - Disclosure - Fair Value Measurements (Details) - Financial Instruments link:presentationLink link:calculationLink link:definitionLink 9955538 - Disclosure - Allowance for Expected Credit Losses (Details) - Changes in the Allowance for Expected Credit Losses on Premiums Receivable link:presentationLink link:calculationLink link:definitionLink 9955539 - Disclosure - Allowance for Expected Credit Losses (Details) - Changes in the Allowance for Estimated Uncollectible Reinsurance link:presentationLink link:calculationLink link:definitionLink 9955540 - Disclosure - Allowance for Expected Credit Losses (Details) - Narrative link:presentationLink link:calculationLink link:definitionLink 9955541 - Disclosure - Allowance for Expected Credit Losses (Details) - Changes in the Allowance for Expected Credit Losses on Contractholder Receivables (Details) link:presentationLink link:calculationLink link:definitionLink 9955542 - Disclosure - Goodwill and Other Intangible Assets (Details) link:presentationLink link:calculationLink link:definitionLink 9955543 - Disclosure - Goodwill and Other Intangible Assets (Details) - Other Intangible Assets link:presentationLink link:calculationLink link:definitionLink 9955543 - Disclosure - Goodwill and Other Intangible Assets (Details) - Other Intangible Assets link:presentationLink link:calculationLink link:definitionLink 9955544 - Disclosure - Insurance Claim Reserves (Details) - Reserve Detail for Claims and Claim Adjustment Expenses link:presentationLink link:calculationLink link:definitionLink 9955545 - Disclosure - Insurance Claim Reserves (Details) - Prior Year Reserve Development link:presentationLink link:calculationLink link:definitionLink 9955546 - Disclosure - Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) (Details) link:presentationLink link:calculationLink link:definitionLink 9955547 - Disclosure - Other Comprehensive Income (Loss) and Accumulated Other Comprehensive Income (Loss) (Details) - Reclassifications link:presentationLink link:calculationLink link:definitionLink 9955548 - Disclosure - Common Share Repurchases (Details) link:presentationLink link:calculationLink link:definitionLink 9955549 - Disclosure - Earnings per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Share-Based Incentive Compensation (Details) link:presentationLink link:calculationLink link:definitionLink 9955551 - Disclosure - Pension Plans, Retirement Benefits and Savings Plans (Details) link:presentationLink link:calculationLink link:definitionLink 9955552 - Disclosure - Leases (Details) link:presentationLink link:calculationLink link:definitionLink 9955553 - Disclosure - Contingencies, Commitments and Guarantees (Details) - Commitments link:presentationLink link:calculationLink link:definitionLink 9955554 - Disclosure - Contingencies, Commitments and Guarantees (Details) - Guarantees link:presentationLink link:calculationLink link:definitionLink 9955555 - Disclosure - Noncash Investing and Financing Activities (Details) link:presentationLink link:calculationLink link:definitionLink