0000001 - Document - Cover link:presentationLink link:calculationLink link:definitionLink 0000002 - Document - Audit Information link:presentationLink link:calculationLink link:definitionLink 9952151 - Statement - Consolidated Balance Sheets link:presentationLink link:calculationLink link:definitionLink 9952152 - Statement - Consolidated Balance Sheets (Parenthetical) link:presentationLink link:calculationLink link:definitionLink 9952153 - Statement - Consolidated Statements of Income link:presentationLink link:calculationLink link:definitionLink 9952154 - Statement - Consolidated Statements of Comprehensive Income link:presentationLink link:calculationLink link:definitionLink 9952155 - Statement - Consolidated Statements of Changes in Equity link:presentationLink link:calculationLink link:definitionLink 9952156 - Statement - Consolidated Statements of Cash Flows link:presentationLink link:calculationLink link:definitionLink 9952157 - Disclosure - Nature of business and organization structure link:presentationLink link:calculationLink link:definitionLink 9952158 - Disclosure - Summary of significant accounting policies link:presentationLink link:calculationLink link:definitionLink 9952159 - Disclosure - Investments link:presentationLink link:calculationLink link:definitionLink 9952160 - Disclosure - Fair Value link:presentationLink link:calculationLink link:definitionLink 9952161 - Disclosure - Loss Reserves link:presentationLink link:calculationLink link:definitionLink 9952162 - Disclosure - Reinsurance link:presentationLink link:calculationLink link:definitionLink 9952163 - Disclosure - Borrowings link:presentationLink link:calculationLink link:definitionLink 9952164 - Disclosure - Income Taxes link:presentationLink link:calculationLink link:definitionLink 9952165 - Disclosure - Employee benefits link:presentationLink link:calculationLink link:definitionLink 9952166 - Disclosure - Share-based compensation link:presentationLink link:calculationLink link:definitionLink 9952167 - Disclosure - Related party transactions link:presentationLink link:calculationLink link:definitionLink 9952168 - Disclosure - Commitments and contingencies link:presentationLink link:calculationLink link:definitionLink 9952169 - Disclosure - Stockholders' Equity link:presentationLink link:calculationLink link:definitionLink 9952170 - Disclosure - Accumulated Other Comprehensive Income (Loss) link:presentationLink link:calculationLink link:definitionLink 9952171 - Disclosure - Statutory Information link:presentationLink link:calculationLink link:definitionLink 9952172 - Disclosure - Earnings Per Share link:presentationLink link:calculationLink link:definitionLink 9952173 - Disclosure - Segment Reporting link:presentationLink link:calculationLink link:definitionLink 9952174 - Disclosure - Schedule I, Summary of Investments - Other than Investments in Related Parties link:presentationLink link:calculationLink link:definitionLink 9952175 - Disclosure - Schedule II - Parent Company Only link:presentationLink link:calculationLink link:definitionLink 9955511 - Disclosure - Summary of significant accounting policies (Policies) link:presentationLink link:calculationLink link:definitionLink 9955512 - Disclosure - Investments (Tables) link:presentationLink link:calculationLink link:definitionLink 9955513 - Disclosure - Fair Value (Tables) link:presentationLink link:calculationLink link:definitionLink 9955514 - Disclosure - Loss Reserves (Tables) link:presentationLink link:calculationLink link:definitionLink 9955515 - Disclosure - Reinsurance (Tables) link:presentationLink link:calculationLink link:definitionLink 9955516 - Disclosure - Borrowings (Tables) link:presentationLink link:calculationLink link:definitionLink 9955517 - Disclosure - Income Taxes (Tables) link:presentationLink link:calculationLink link:definitionLink 9955518 - Disclosure - Share-based compensation (Tables) link:presentationLink link:calculationLink link:definitionLink 9955519 - Disclosure - Related party transactions (Tables) link:presentationLink link:calculationLink link:definitionLink 9955520 - Disclosure - Commitments and contingencies (Tables) link:presentationLink link:calculationLink link:definitionLink 9955521 - Disclosure - Equity (Tables) link:presentationLink link:calculationLink link:definitionLink 9955522 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) link:presentationLink link:calculationLink link:definitionLink 9955523 - Disclosure - Statutory Information (Tables) link:presentationLink link:calculationLink link:definitionLink 9955524 - Disclosure - Earnings Per Share (Tables) link:presentationLink link:calculationLink link:definitionLink 9955525 - Disclosure - Schedule II - Parent Company Only (Tables) link:presentationLink link:calculationLink link:definitionLink 9955526 - Disclosure - Nature of business and organization structure (Details) link:presentationLink link:calculationLink link:definitionLink 9955527 - Disclosure - Summary of significant accounting policies (Details) link:presentationLink link:calculationLink link:definitionLink 9955528 - Disclosure - Investments - Net Investment Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955529 - Disclosure - Investments - Net Investment Gains (Losses) (Details) link:presentationLink link:calculationLink link:definitionLink 9955530 - Disclosure - Investments - Net Unrealized Gains and Losses on Available-for-Sale Securities as a Separate Component of OCI (Details) link:presentationLink link:calculationLink link:definitionLink 9955531 - Disclosure - Investments - Change in Net Unrealized Gains (Losses) on Available-for-Sale Securities (Details) link:presentationLink link:calculationLink link:definitionLink 9955532 - Disclosure - Investments - Summary of Fixed Maturity Securities Classified as Available-for-Sale (Details) link:presentationLink link:calculationLink link:definitionLink 9955533 - Disclosure - Investments - Schedule of Fixed Maturity Securities in an Continuous Unrealized Loss Position (Details) link:presentationLink link:calculationLink link:definitionLink 9955534 - Disclosure - Investments - Summary of Contractual Maturities of Fixed Maturity Securities Available-For-Sale (Details) link:presentationLink link:calculationLink link:definitionLink 9955535 - Disclosure - Investments - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955536 - Disclosure - Fair Value - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955537 - Disclosure - Fair Value - Summary of Significant Inputs used for Fair Value Measurement of Fixed Maturity Securities (Details) link:presentationLink link:calculationLink link:definitionLink 9955538 - Disclosure - Fair Value - Schedule of Fair Value Assets Measured on Recurring Basis (Details) link:presentationLink link:calculationLink link:definitionLink 9955539 - Disclosure - Fair Value - Schedule of Additional Information about Fair Value Assets Measured on Recurring Basis, Unobservable Input Reconciliation (Details) link:presentationLink link:calculationLink link:definitionLink 9955540 - Disclosure - Fair Value - Summary of Fair Value Assets Measured on Recurring Basis, Significant Unobservable Input (Details) link:presentationLink link:calculationLink link:definitionLink 9955541 - Disclosure - Fair Value - Schedule of Estimated Fair Value Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9955542 - Disclosure - Loss reserves - Summary of Liability For Unpaid Claims And Claim Adjustment Expenses (Details) link:presentationLink link:calculationLink link:definitionLink 9955543 - Disclosure - Loss Reserves - Activity for the Liability for Loss Reserves (Details) link:presentationLink link:calculationLink link:definitionLink 9955544 - Disclosure - Loss Reserves - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955545 - Disclosure - Loss Reserves - IBNR Liabilities and Expected Development on Reported Claims (Details) link:presentationLink link:calculationLink link:definitionLink 9955546 - Disclosure - Loss Reserves - Paid Claims Development, Net of Reinsurance (Details) link:presentationLink link:calculationLink link:definitionLink 9955547 - Disclosure - Loss Reserves - Average Payout of Incurred Claims by Age (Details) link:presentationLink link:calculationLink link:definitionLink 9955548 - Disclosure - Reinsurance - Summary of Effects of Reinsurance on Premiums Written and Earned (Details) link:presentationLink link:calculationLink link:definitionLink 9955549 - Disclosure - Reinsurance - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955549 - Disclosure - Reinsurance - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Reinsurance - Schedule of Retained Aggregate Loss and Initial and Current Reinsurance Coverage (Details) link:presentationLink link:calculationLink link:definitionLink 9955550 - Disclosure - Reinsurance - Schedule of Retained Aggregate Loss and Initial and Current Reinsurance Coverage (Details) link:presentationLink link:calculationLink link:definitionLink 9955551 - Disclosure - Reinsurance - Quota Share Reinsurance (Details) link:presentationLink link:calculationLink link:definitionLink 9955551 - Disclosure - Reinsurance - Quota Share Reinsurance (Details) link:presentationLink link:calculationLink link:definitionLink 9955552 - Disclosure - Borrowings - Schedule of Long-term Borrowings (Details) link:presentationLink link:calculationLink link:definitionLink 9955553 - Disclosure - Borrowings - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955554 - Disclosure - Income Taxes - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955555 - Disclosure - Income Taxes - Provision for Income Taxes (Details) link:presentationLink link:calculationLink link:definitionLink 9955556 - Disclosure - Income Taxes - Tax Rate Reconciliation (Details) link:presentationLink link:calculationLink link:definitionLink 9955557 - Disclosure - Income Taxes - Deferred Tax Assets and Liabilities (Details) link:presentationLink link:calculationLink link:definitionLink 9955558 - Disclosure - Employee benefits (Details) link:presentationLink link:calculationLink link:definitionLink 9955559 - Disclosure - Share-based compensation - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955560 - Disclosure - Share-based compensation - Status of EHI Equity Based Awards (Details) link:presentationLink link:calculationLink link:definitionLink 9955561 - Disclosure - Share-based compensation - Cash Award Activity (Details) link:presentationLink link:calculationLink link:definitionLink 9955562 - Disclosure - Share-based compensation - Status of Other Equity Based Awards (Details) link:presentationLink link:calculationLink link:definitionLink 9955563 - Disclosure - Related party transactions - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955564 - Disclosure - Related party transactions - Schedule of Related Party Transactions (Details) link:presentationLink link:calculationLink link:definitionLink 9955565 - Disclosure - Commitments and contingencies - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955566 - Disclosure - Commitments and contingencies - Operating Lease Maturity (Details) link:presentationLink link:calculationLink link:definitionLink 9955566 - Disclosure - Commitments and contingencies - Operating Lease Maturity (Details) link:presentationLink link:calculationLink link:definitionLink 9955567 - Disclosure - Stockholders' Equity (Details) link:presentationLink link:calculationLink link:definitionLink 9955568 - Disclosure - Stockholders' Equity - Dividends Declared (Details) link:presentationLink link:calculationLink link:definitionLink 9955569 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Schedule of Accumulated Other Comprehensive Income (Loss) (Details) link:presentationLink link:calculationLink link:definitionLink 9955570 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Reclassification out of Accumulated Other Comprehensive Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955571 - Disclosure - Statutory Information (Details) link:presentationLink link:calculationLink link:definitionLink 9955572 - Disclosure - Statutory Information - Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955573 - Disclosure - Earnings Per Share (Details) link:presentationLink link:calculationLink link:definitionLink 9955574 - Disclosure - Schedule I, Summary of Investments - Other than Investments in Related Parties (Details) link:presentationLink link:calculationLink link:definitionLink 9955575 - Disclosure - Schedule II - Parent Company Only - Balance Sheet (Details) link:presentationLink link:calculationLink link:definitionLink 9955576 - Disclosure - Schedule II - Parent Company Only - Statements of Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955577 - Disclosure - Schedule II - Parent Company Only - Statements of Comprehensive Income (Details) link:presentationLink link:calculationLink link:definitionLink 9955578 - Disclosure - Schedule II - Parent Company Only - Statements of Cash Flows (Details) link:presentationLink link:calculationLink link:definitionLink 9955579 - Disclosure - Schedule II - Parent Company Only - Notes to Schedule II Narrative (Details) link:presentationLink link:calculationLink link:definitionLink 9955580 - Disclosure - Schedule II - Parent Company Only - Notes to Schedule II Schedule of Borrowings (Details) link:presentationLink link:calculationLink link:definitionLink