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Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture Shares Issued, Shares, Share-Based Payment Arrangement, before Forfeiture Deferred tax losses, operating loss carryforward Deferred Tax Losses, Operating Loss Carryforward Deferred Tax Losses, Operating Loss Carryforward Losses and loss adjustment expenses: Policyholder Benefits and Claims Incurred, Net [Abstract] Due after ten years, Cost or Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 10 Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Change in unrealized gains or losses Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss) Disclosure of Share-Based Compensation Arrangements by Share-Based Payment Award Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Concentrations of Credit Risk Concentration Risk Disclosure [Text Block] Investment, Identifier [Axis] Investment, Identifier [Axis] Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Total Debt, Long-Term and Short-Term, Combined Amount Insurance Gross Amount Direct Premiums Earned Apollo, Class A & B Notes Class A & B Notes [Member] Class A & B Notes Number of investments in VIEs Number of investments Number Of Investments In Variable Interest Entities Number Of Investments In Variable Interest Entities Retirement Benefits [Abstract] Retirement Benefits [Abstract] Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Auditor infomation [Abstract] Auditor infomation Income from operations before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income (Loss) from Continuing Operations before 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and Fixtures [Member] Award Type [Axis] Award Type [Axis] Schedule of Dividends Payable Schedule of Dividends Payable [Table Text Block] Cumulative foreign currency translation adjustments: Accumulated Foreign Currency Adjustment Attributable to Parent [Member] Parent Company Parent Company [Member] Deferred acquisition costs Increase (Decrease) in Deferred Policy Acquisition Costs Due for settlement Premiums Receivable Non Current Premiums receivable non current Investment, Name [Domain] Investment, Name [Domain] Accounting for Share-Based Payments and Long-Term Incentive Plans Share-Based Payment Arrangement [Policy Text Block] Trading Symbol Trading Symbol Liability, Payments, Due year four Lessee, Operating Lease, Liability, to be Paid, Year Four Accounting for Business Combinations Business Combination [Policy Text Block] Credit rating, major rating agencies [Domain] Credit rating, major rating agencies [Domain] Credit rating, major rating agencies Effective Income Tax Rate 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Allowance for Credit Loss Percentage of reinsurance liabilities Percentage Of Reinsurance Liabilities Percentage of reinsurance liabilities Fair Value of Derivative Instruments Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table Text Block] Total, Fair Market Value Debt Securities, Available for Sale, Continuous Loss Position, Fair Market Value Debt Securities, Available for Sale, Continuous Loss Position, Fair Market Value Global corporate securities Global corporate securities [Member] Global corporates Exercise Price Award Exercise Price Entity Filer Category Entity Filer Category Class of Stock [Domain] Class of Stock [Domain] Privately-held investments — Available for sale Privately-held investments, Available for Sale [Member] Privately-held investments, Available for Sale Dividend Payment Restrictions [Text Block] Dividend Payment Restrictions [Text Block] Income tax benefit at statutory tax rate Effective Income Tax Rate Reconciliation, at 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Securities, Available-for-Sale, Allowance for Credit Loss Securities Below Investment Grade or NR Debt Securities, Available for Sale, Unrealized Loss Position, Accumulated Loss, Securities Below Investment Grade or NR Debt Securities, Available for Sale, Unrealized Loss Position, Accumulated Loss, Securities Below Investment Grade or NR Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability Short-Duration Insurance Contracts, Reconciliation of Claims Development to Liability [Table Text Block] Preferred Stock, Dividend Rate, Percentage Preference shares, rate Preferred Stock, Dividend Rate, Percentage Other Comprehensive Income: Other Comprehensive Income Loss [Abstract] Other Comprehensive Income Loss Sale of Stock [Axis] Sale of Stock [Axis] Gross Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Preference share dividends Dividends on preference shares Redeemable Preferred Stock Dividends Award Type 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