0000001 - Document - Cover Page link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - CONSOLIDATED STATEMENTS OF FINANCIAL POSITION link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - CONSOLIDATED STATEMENTS OF FINANCIAL POSITION (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) link:presentationLink link:calculationLink link:definitionLink 9952156 - Statement - CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952157 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS (UNAUDITED) link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Nature of Operations link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Significant Accounting Policies link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Revenue link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Segment Information link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Earnings Per Share link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Fair Value link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Investments link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Bank Line of Credit link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Postretirement Benefits link:presentationLink link:calculationLink link:definitionLink 9952167 - Disclosure - Income Taxes link:presentationLink link:calculationLink link:definitionLink 9952168 - Disclosure - Capital Stock link:presentationLink link:calculationLink link:definitionLink 9952169 - Disclosure - Accumulated Other Comprehensive Income (Loss) link:presentationLink link:calculationLink link:definitionLink 9952170 - Disclosure - Concentrations of Credit Risk link:presentationLink link:calculationLink link:definitionLink 9952171 - Disclosure - Commitments and Contingencies link:presentationLink link:calculationLink link:definitionLink 9952172 - Disclosure - Subsequent Events link:presentationLink link:calculationLink link:definitionLink 9955511 - Disclosure - Significant Accounting Policies (Policies) link:presentationLink link:calculationLink link:definitionLink 9955512 - Disclosure - Revenue (Tables) link:presentationLink link:calculationLink link:definitionLink 9955513 - Disclosure - Segment Information (Tables) link:presentationLink link:calculationLink link:definitionLink 9955514 - Disclosure - Earnings Per Share (Tables) link:presentationLink link:calculationLink link:definitionLink 9955515 - 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Disclosure - Investments - Cost and Fair Value, Net of Credit Loss Allowance, of Fixed Maturity Securities (Details) link:presentationLink link:calculationLink link:definitionLink 9955530 - Disclosure - Investments - Amortized Cost and Estimated Fair Value, Net of Credit Loss Allowance, of Fixed Maturity Securities by Contractual Maturity (Details) link:presentationLink link:calculationLink link:definitionLink 9955531 - Disclosure - Investments - Available-For-Sale Securities in a Gross Unrealized Loss Position by Length of Time (Details) link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Investments - Allowance for Credit Losses (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Investments - Net Investment Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955534 - Disclosure - Investments - Net Realized and Unrealized Investment Gains (Details) link:presentationLink link:calculationLink link:definitionLink 9955535 - Disclosure - Investments - Portion of Net Unrealized Gains (Losses) Recognized During the Reporting Period (Details) link:presentationLink link:calculationLink link:definitionLink 9955536 - Disclosure - Investments - Impairments on Investments (Details) link:presentationLink link:calculationLink link:definitionLink 9955537 - Disclosure - Investments - Securities Lending Transactions (Details) link:presentationLink link:calculationLink link:definitionLink 9955538 - Disclosure - Bank Line of Credit (Details) link:presentationLink link:calculationLink link:definitionLink 9955539 - Disclosure - Postretirement Benefits - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955540 - Disclosure - Postretirement Benefits - Pension Plan Cost (Income) (Details) link:presentationLink link:calculationLink link:definitionLink 9955541 - Disclosure - Income Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9955542 - Disclosure - Capital Stock - Class A and B Common Stock (Details) link:presentationLink link:calculationLink link:definitionLink 9955543 - Disclosure - Capital Stock - Stock Repurchases (Details) link:presentationLink link:calculationLink link:definitionLink 9955544 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Details) link:presentationLink link:calculationLink link:definitionLink 9955545 - Disclosure - Concentrations of Credit Risk (Details) link:presentationLink link:calculationLink link:definitionLink 9955546 - Disclosure - Commitments and Contingencies (Details) link:presentationLink link:calculationLink link:definitionLink