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Claims and Claims Adjustment Expense [Roll Forward] Other asset-backed securities Asset-Backed Securities [Member] Consolidation Items [Axis] Consolidation Items [Axis] Variable Rate [Axis] Variable Rate [Axis] Counterparty Name [Axis] Counterparty Name [Axis] Deferred tax liabilities: Components of Deferred Tax Liabilities [Abstract] Total investment income Gross Investment Income, Operating Maturities, calls and paydowns of fixed maturity securities held-to-maturity Proceeds from Maturities, Prepayments and Calls of Held-to-Maturity Securities Fixed maturity securities, held-to-maturity, at amortized cost (net of allowance for credit losses of $468 and $243, respectively) Debt Securities, Held-to-Maturity, Excluding Accrued Interest, after Allowance for Credit Loss Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate securities and miscellaneous Corporate Debt Securities [Member] Accounting Standards Update 2016-13 [Member]