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Accrued expenses and other liabilities Increase (Decrease) In Accrued Expenses And Other Liabilities Increase (Decrease) in Accrued expenses and other liabilities. Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Cash and Cash Equivalents at Beginning of Period Cash and Cash Equivalents at End of Period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Rollforward of allowance for mortgage loan losses: Financing Receivable, Allowance for Credit Loss [Roll Forward] Measurement Frequency [Domain] Measurement Frequency [Domain] Stock-based compensation expense Share-Based Payment Arrangement, Noncash Expense Net lease expense Lease, Cost LEASE COMMITMENTS Lessee, Operating Leases [Text Block] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Due after five years through 10 years Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, after Year 5 Through 10 Basic (in dollars per share) Basic - net (in dollars per share) Earnings Per Share, Basic Statistical Measurement [Axis] Statistical Measurement [Axis] Insider Trading Arrangements [Line Items] Award Type [Axis] Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Retained earnings Retained Earnings (Accumulated Deficit) Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Real Estate, Type of Property [Axis] Real Estate, Type of Property [Axis] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common stock Common Stock [Member] Recoveries of amounts previously written off, if any Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss, Recovery Operating lease expense Operating Lease, Cost Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization, Consolidation and Presentation of Financial Statements Disclosure and Significant Accounting Policies [Text Block] Cover [Abstract] Cover [Abstract] Insurance [Abstract] Percent of Total Concentration Risk, Percentage Concentration Risk Benchmark [Axis] Concentration Risk Benchmark [Axis] Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] Reinsurance Recoverable, Allowance for Credit Loss [Roll Forward] AOCI Attributable to Parent [Abstract] Equity Awards Adjustments Equity Awards Adjustments [Member] Financial Asset, Past Due Financial Asset, Past Due [Member] Available-for-sale Debt Securities, Available-for-Sale, Realized Gain (Loss) Total liabilities and stockholders' equity Liabilities and Equity Basic and Diluted Earnings per Share [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Net investment gains (losses) Total net investment gains (losses) Realized Investment Gains (Losses) Stock Options Options Awards Share-Based Payment Arrangement, Option [Member] Total reclassification adjustments, before tax Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Other, net Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Related and Nonrelated Parties [Domain] Related and Nonrelated Parties [Domain] Premiums receivable Increase (Decrease) in Premiums Receivable Tabular List, Table Tabular List [Table Text Block] Summary of Unrealized Gain and Loss Unrealized Gain (Loss) on Investments [Table Text Block] Reinsurance receivables Increase (Decrease) in Reinsurance Recoverable RESERVES FOR LOSSES AND LOSS SETTLEMENT EXPENSES Liability for Future Policy Benefits and Unpaid Claims Disclosure [Text Block] Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Summary of Rollforward of Credit Loss Allowance for Reinsurance Receivable Reinsurance Recoverable, Allowance for Credit Loss [Table Text Block] Debt-to-Value [Axis] Debt-to-Value [Axis] Summary of Proceeds and Gross Realized Gains (Losses) Schedule of Realized Gain (Loss) [Table Text Block] East North Central East North Central [Member] East North Central [Member] Adjustment to Compensation: Adjustment to Compensation [Axis] Commercial mortgage-backed Commercial mortgage-backed Commercial Mortgage-Backed Securities [Member] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total Assets Measured at Fair Value Level 3 assets Assets, Fair Value Disclosure Name Measure Name Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] Liability for Unpaid Claims and Claims Adjustment Expense [Roll Forward] INCOME TAX Income Tax Disclosure [Text Block] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Less than 12 months Debt Securities, Available-for-Sale, Continuous Unrealized Loss Position, Less than 12 Months, Number of Positions Debt Instrument [Line Items] Debt Instrument [Line Items] Other long-term investments Gain (Loss) on Sale of Other Investments Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Additional paid-in capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Total Debt Securities, Available-for-Sale, Unrealized Loss Position Total investment income Investment Income, Gross Investment Income, Gross Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Net investment gains (losses): Realized Investment Gains (Losses) [Abstract] Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Company Selected Measure Amount Company Selected Measure Amount Financial Asset, Aging [Axis] Financial Asset, Aging [Axis] Income taxes receivable Income Taxes Receivable Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Depreciation and amortization Depreciation, Depletion and Amortization Stock based compensation (in shares) Shares Issued, Shares, Share-Based Payment Arrangement, after Forfeiture Non-PEO NEO Non-PEO NEO [Member] 9% UFG Notes - Series A & B Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Total benefits, losses and expenses Benefits, Losses and Expenses Income tax expense (benefit) Income tax expense (benefit) Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] AVAILABLE-FOR-SALE Available-for-Sale Securities, Continuous Unrealized Loss Position, Qualitative Disclosure [Abstract] Net Change in Cash and Cash Equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Accrued expenses and other liabilities Accrued expenses and other liabilities Accrued expenses and other liabilities. Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Premiums receivable (net of allowance for doubtful accounts of $2,508 and $1,899) Premiums Receivable, Net Accumulated Other Comprehensive Income (Loss) [Roll Forward] AOCI Attributable to Parent, Net of Tax [Roll Forward] Net Income (loss) Net Income (loss) Net income (loss) Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] Financing Receivable, Past Due [Table] Financing Receivable, Past Due [Table] Restatement Determination Date: Restatement Determination Date [Axis] Summary of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Amortization of deferred policy acquisition costs Deferred Policy Acquisition Cost, Amortization Expense and Amortization of Value of Business Acquired (VOBA) Deferred Policy Acquisition Cost, Amortization Expense and Amortization of Value of Business Acquired (VOBA) Interest on fixed maturities Investment Income, Interest Net income (loss) Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent Net purchases and sales of property and equipment Payments for (Proceeds from) Productive Assets East South Central East South Central [Member] East South Central [Member] Income taxes payable Accrued Income Taxes Revenues Revenues [Abstract] Current Current Federal Tax Expense (Benefit) Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Income on other long-term investments Other Long-Term Investments [Member]