10. Segment Information [Abstract] 10. Segment Information [Abstract] Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Business Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Annuity Segment Annuity Segment [Member] Annuity Segment [Member] Life Insurance Segment Life Insurance Product Line [Member] Indefinite-lived Intangible Assets [Line Items] Indefinite-lived Intangible Assets [Line Items] Goodwill Goodwill Investment Operations [Abstract] Investment Operations [Abstract] Schedule of Gain (Loss) on Securities [Table] Schedule of Gain (Loss) on Securities [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] Accounting Standards Update 2016-01 Accounting Standards Update 2016-01 [Member] Impairments by type [Axis] Impairments by type [Axis] Impairments by type [Axis] Total impairments on investments [Domain] Total impairments on investments [Domain] Total impairments on investments [Domain] Other credit-related Other credit related impairments [Member] Amount represents credit-related losses for mortgage loans, real estate and fixed maturities written down to fair value. Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Debt Securities Debt Securities [Member] Equity Securities Equity Securities [Member] Debt Security Category [Axis] Debt Security Category [Axis] Gain (Loss) on Investments, Including Marketable Securities and Investments Held at Cost, Categories of Investments [Domain] Other than Temporary Impairment, Credit Losses Recognized in Earnings, Categories of Investments [Domain] Categories of Investments, Marketable Securities, Available-for-sale Securities Available-for-sale Securities [Member] Cost-method Investments Cost-method Investments [Member] Gain (Loss) on Securities [Line Items] Gain (Loss) on Securities [Line Items] Gross gains - fixed maturities - available for sale Available-for-sale Securities, Gross Realized Gains Available-for-sale Securities, Gross Realized Losses Available-for-sale Securities, Gross Realized Losses Gain (Loss) on Sales of Loans, Net Gain (Loss) on Sales of Loans, Net Realized Gain (Loss) on Disposition of Other Financial Assets Gain (Loss) on Disposition of Other Financial Assets Realized Gains (Loss) on sales of investments Realized gains (losses) on sales of investments Realized gains (losses) on sales of investments Net realized capital gains on sales of investments Gain (Loss) on Investments, Excluding Other than Temporary Impairments Realized Gain (Loss) on sales of Equity Securities Available-for-sale Securities, Gross Realized Gain (Loss), Excluding Other than Temporary Impairments New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Operating Results Net impairment loss recognized in earnings Other than Temporary Impairment Losses, Investments, Portion Recognized in Earnings, Net Realized gains (losses) on investments recorded in income Gain (Loss) on Investments Proceeds from Sale of Available-for-sale Securities Proceeds from Sale of Debt Securities, Available-for-sale Income Statement [Abstract] Statement [Table] Statement [Table] Dividends [Axis] Dividends [Axis] Dividends [Domain] Dividends [Domain] Statement [Line Items] Statement [Line Items] Revenues: Revenues [Abstract] Interest sensitive product charges Insurance Commissions and Fees Traditional life insurance premiums Premiums Earned, Net, Life Net investment income Net Investment Income Net realized capital gains (losses) Net other-than-temporary impairment losses recognized in earnings Other income Other Income Total revenues Revenues Benefits and expenses: Benefits, Losses and Expenses [Abstract] Interest sensitive product benefits Interest Sensitive and Index Product Benefits Interest Sensitive and Index Product Benefits, including interest credited to policyholder account balances, index credits, amortization of deferred sales inducements, and death benefits related to interest sensitive products (annuity and universal life). Traditional life insurance benefits Policyholder Benefits and Claims Incurred, Net Policyholder dividends Policyholder Dividends, Expense Underwriting, acquisition and insurance expenses Selling, General and Administrative Expense Interest expense Interest Expense Other expenses Other Cost and Expense, Operating Total benefits and expenses Benefits, Losses and Expenses Income before equity method investments, income taxes and noncontrolling interest Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Income taxes Income Tax Expense (Benefit) Equity income, net of related income taxes Income (Loss) from Equity Method Investments Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net (income) loss attributable to noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest Net income attributable to FBL Financial Group, Inc. Net Income (Loss) Attributable to Parent Earnings per common share Earnings Per Share, Basic Earnings per common share - assuming dilution Earnings Per Share, Diluted Commitments and Contingencies Disclosure [Abstract] Other Commitments [Table] Other Commitments [Table] Investment Type [Axis] Investment Type [Axis] Investments [Domain] Investments [Domain] Limited partnership Limited partnership [Member] Limited partnership [Member] Private Placement Private Placement [Member] Other Assets Other Assets [Member] Fixed Maturities Fixed Maturities [Member] Other Commitments [Line Items] Other Commitments [Line Items] Other Commitment Other Commitment Debt Disclosure [Abstract] Defined Benefit Plan [Abstract] Defined Benefit Plan [Abstract] Schedule of Net Benefit Costs [Table Text Block] Schedule of Net Benefit Costs [Table Text Block] Financing Receivable, Allowance for Credit Loss [Table] Financing Receivable, Allowance for Credit Loss [Table] Class of Financing Receivable [Axis] Class of Financing Receivable [Axis] Class of Financing Receivable [Domain] Class of Financing Receivable [Domain] Financing Receivable, Allowance for Credit Loss [Line Items] Financing Receivable, Allowance for Credit Loss [Line Items] Balance at beginning of period Financing Receivable, Allowance for Credit Loss Charge offs (Recoveries) Financing Receivable, Allowance for Credit Loss, Writeoff Balance at end of period Segment Information [Abstract] Segment Information [Abstract] Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Reconciliation of Revenue from Segments to Consolidated [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Schedule of Segment Reporting Information, by Segment [Table Text Block] Reconciliation of Non-GAAP measures [Table Text Block] Reconciliation of non-GAAP measures [table text block] [Table Text Block] Reconciliation of non-GAAP measures used to my management to evaluate segment performance to corresponding line items in our GAAP financial statements [Table Text Block] Earnings Per Share [Abstract] Earnings Per Share Earnings Per Share [Text Block] Fair Values [Abstract] Fair Values [Abstract] Fair Value Measurement Inputs and Valuation Techniques [Table] Fair Value Measurement Inputs and Valuation Techniques [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Estimate of Fair Value Measurement Estimate of Fair Value Measurement [Member] Fair Value, Valuation Source [Axis] Fair Value, Valuation Source [Axis] Fair Value, Valuation Source [Axis] Valuation Source [Domain] Valuation Source [Domain] Valuation Source [Domain] Third-party vendors Third-party Vendor [Member] Third-party Vendor valuation source [Member] Priced internally Internally priced [Member] Internally priced valuation source [Member] Corporate Securities Corporate Debt Securities [Member] Residential mortgage-backed securities Residential Mortgage Backed Securities [Member] Commercial mortgage-backed securities Commercial Mortgage Backed Securities [Member] Other asset backed securities Asset-backed Securities, Securitized Loans and Receivables [Member] Collateralized Debt Obligations Collateralized Debt Obligations [Member] Non-redeemable preferred stock Nonredeemable Preferred Stock [Member] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Recurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Fair Value, Inputs, Level 3 Fair Value, Inputs, Level 3 [Member] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Fair Value Measurement Inputs and Valuation Techniques [Line Items] Assets, Fair Value Disclosure Assets, Fair Value Disclosure Available-for-sale Securities Available-for-sale Securities percent of total percent of total Percent of total fixed maturities Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table] Reconciliation of Other Significant Reconciling Items from Segments to Consolidated [Table] Life insurance - interest sensitive Life insurance - interest sensitive [Member] Life insurance - interest sensitive [Member] Life insurance - traditional Life insurance - traditional [Member] Life insurance - traditional [Member] Corporate and Other Corporate and Other [Member] Policy charges [Axis] Policy charges [Axis] Policy charges - detail by type of charge [Axis] Policy Charges [Domain] Policy Charges [Domain] Policy Charges [Domain] Cost of insurance charges & Administration charges [Member] Cost of insurance charges & Administration charges [Member] Cost of insurance charges & Administration charges [Member] Admin charges Admiin charges [Member] Admiin charges [Member] Cost of insurance charges Cost of insurance charges [Member] Cost of insurance charges [Member] Surrender charges Surrender charges [Member] Surrender charges [Member] Separate account charges Separate account charges [Member] Separate account charges [Member] Amortization of policy initiation fees Amortization of policy initiation fees [Member] Amortization of policy initiation fees for bonus premiums or bonus interest that was deferred upon policy initiation. [Member] Segment Reporting, Other Significant Reconciling Item [Line Items] Segment Reporting, Other Significant Reconciling Item [Line Items] Premiums collected Proceeds from Insurance Premiums Collected Change in due premiums and other Increase (Decrease) in Premiums Receivable Net realized gains/losses on investments & change in fair value of derivatives on amortization of unearned revenue reserves Net realized gains/losses on investments & change in fair value of derivatives on amortization of unearned revenue reserves Net realized gains/losses on investments & change in fair value of derivatives on amortization of unearned revenue reserves Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Liability Class [Axis] Liability Class [Axis] Fair Value by Liability Class [Domain] Fair Value by Liability Class [Domain] Index Product Embedded Derivatives Index Product Embedded Derivatives [Member] Index Product Embedded Derivatives included in future policy benefits [Member] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Asset Balance, beginning of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases Disposals Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Sales Realized and unrealized gains (losses), net, included in net income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings Realized and unrealized gains (losses), net, included in other comprehensive income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) Transfers Into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3 Amortization included in net income Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset, Amortization Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset, Amortization Asset Balance, end of period Liability balance, beginning of period Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Purchases Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Settlements Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements Realized and unrealized gains (losses), net, included in net income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Realized and unrealized gains (losses), net, included in other comprehensive income Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Other Comprehensive Income (Loss) Transfers Into Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers Into Level 3 Transfers out of Level 3 Fair Value, Measurement with Unobservable Inputs Reconciliation, Liability, Transfers out of Level 3 Liability balance, end of period Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Segment Information Segment Reporting Disclosure [Text Block] Affordable Housing Program [Abstract] Affordable Housing Program [Abstract] Summary of Investment Holdings [Table] Summary of Investment Holdings [Table] Investment, Name [Axis] Investment, Name [Axis] Investment, Name [Domain] Investment, Name [Domain] Affordable Housing Tax Credit Investments Affordable Housing Tax Credit Investments [Member] Affordable Housing Tax Credit Investments [Member] Summary of Investment Holdings [Line Items] Summary of Investment Holdings [Line Items] Income Tax Expense (Benefit) Schedule of Defined Benefit Plans Disclosures [Table] Schedule of Defined Benefit Plans Disclosures [Table] Retirement Plan Type [Axis] Retirement Plan Type [Axis] Retirement Plan Type [Domain] Retirement Plan Type [Domain] Pension Plan Pension Plan [Member] Other Pension Plan Other Pension Plan [Member] Defined Benefit Plan Disclosure [Line Items] Defined Benefit Plan Disclosure [Line Items] Service cost Defined Benefit Plan, Service Cost Interest cost Defined Benefit Plan, Interest Cost Expected return on assets Defined Benefit Plan, Expected Return (Loss) on Plan Assets Amortization of prior service cost Defined Benefit Plan, Amortization of Prior Service Cost (Credit) Amortization of actuarial loss Defined Benefit Plan, Amortization of Gain (Loss) Net periodic pension cost Defined Benefit Plan, Net Periodic Benefit Cost (Credit) FBL Financial Group, Inc. share of net periodic pension costs Net periodic pension cost individual entity share Net periodic pension cost individual entity share. Schedule of Short-term Debt [Table] Schedule of Short-term Debt [Table] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Short-Term Debt September 26th [Member] Short-Term Debt September 26th [Member] Short-Term Debt September 26th [Member] Short-Term Debt September 30th [Member] Short-Term Debt September 30th [Member] Short-Term Debt September 30th [Member] Short-term Debt, Type [Axis] Short-term Debt, Type [Axis] Short-term Debt, Type [Domain] Short-term Debt, Type [Domain] Federal Home Loan Bank Advances [Member] Federal Home Loan Bank Advances [Member] Short-term Debt [Line Items] Short-term Debt [Line Items] Short-term Debt Short-term Debt Line of Credit Facility, Interest Rate at Period End Line of Credit Facility, Interest Rate at Period End Recent Accounting Pronouncements [Abstract] Recent Accounting Pronouncements [Abstract] New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Retained Earnings Retained Earnings [Member] Accounting Standards Update 2016-02 Accounting Standards Update 2016-02 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets Cumulative Effect on Retained Earnings, Net of Tax Cumulative Effect on Retained Earnings, Net of Tax New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Basic Earnings Per Share New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Basic Earnings Per Share New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share Operating Lease, Right-of-Use Asset Operating Lease, Right-of-Use Asset Operating Lease, Liability Operating Lease, Liability Net Unrealized Gains Losses [Table] Net Unrealized Gains/Losses with offsets [Table] Accumulated Net Unrealized Investment Gain (Loss) Accumulated net unrealized investment gain AND OTTI [Member] Accumulated net unrealized investment gain AND OTTI [Member] Net Unrealized Gains Losses [Line Items] Net Unrealized Gains Losses [Line Items] Net Unrealized Gains Losses on investments in accumulated other comprehensive income. Includes adjustmetns for assumed changes in amortization patterns and provision for taxes. [Line Items] Unrealized appreciation on fixed maturities available for sale Available-for-sale Securities, Accumulated Gross Unrealized Gain (Loss), before Tax Assumed changes in amortization of DAC Assumed changes in amortization of DAC Adjustment for assumed changes in amortization of DAC on net unrealized appreciation/depreciation on investments Assumed changes in amortization pattern of VIIF Assumed changes in amortization patter of VIIF Adjustment for assumed changes in amortization of VIIF on net unrealized appreciation/depreciation on investments Assumed changes in amortization pattern of URR Assumed changes in amortization patter of URR Adjustment for assumed changes in amortization of Unearned Revenue Reserves on net unrealized appreciation/depreciation on investments Assumed change in policyholder liability Assumed changes in policyholder liability Assumed changes in policyholder liability Provision for deferred income taxes Provision Deferred Income Tax Benefits, Expense This item represents the applicable deferred income tax impacts of cumulative net unrealized gains/losses on fixed maturities available-for-sale, equity securities available-for-sale and derivative instruments net of adjustments related deferred policy acquisition costs, sales inducements, value of insurance inforce and unearned revenue reserves. Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] United States Government and agencies US Treasury and Government [Member] State, municipal and other government US States and Political Subdivisions Debt Securities [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than Twelve Months, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Twelve Months or Longer, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Available-for-sale Securities, Continuous Unrealized Loss Position, Accumulated Loss Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Available-for-sale, Securities in Unrealized Loss Positions, Qualitative Disclosure, Number of Positions Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Issuers Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Issuers Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Issuers Statement of Cash Flows [Abstract] Scenario [Axis] Scenario [Axis] Scenario [Domain] Scenario [Domain] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Net income Adjustments to reconcile net income to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Interest credited to account balances Interest Credited to Policy Owner Account Charges for mortality, surrenders and administration Charges for mortality surrenders and administration Charges to policyholder deposits which reduce future policy benefits but are recorded as earnings for the period. Net realized (gains) losses on investments Realized Investment Gains (Losses) Change in fair value of derivatives Unrealized Gain (Loss) on Derivatives Increase in liabilities for life insurance and other future policy benefits Increase (Decrease) in Life Insurance Liabilities Deferral of acquisition costs Increase (Decrease) in Deferred Policy Acquisition Costs Amortization of deferred acquisition costs and value of insurance in force Amortization of Other Deferred Charges Change in reinsurance recoverable Increase (Decrease) in Reinsurance Recoverable Provision for deferred income taxes Deferred Income Tax Expense (Benefit) Other Other Noncash Income (Expense) Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities Investing activities Net Cash Provided by (Used in) Investing Activities [Abstract] Sales, maturities or repayments: Proceeds from Sale, Maturity and Collection of Investments [Abstract] Fixed maturities - available for sale Proceeds from sale, maturity or repayments of Available-for-sale Securities, Debt The cash inflow associated with the sale, maturities (principal being due), prepayments and calls (requests of early payments) on debt securities classified as available-for-sale securities. Equity securities - available for sale Proceeds from Sale of Available-for-sale Securities, Equity Mortgage loans Proceeds from Sale and Collection of Mortgage Notes Receivable Derivative instruments Proceeds from Derivative Instrument, Investing Activities Policy loans Proceeds from Collection of Policy Loans Securities and indebtedness of related parties Proceeds from Sale of Equity Method Investments Other long-term investments Proceeds from Sale and Maturity of Other Investments Acquisitions: Payments to Acquire Investments [Abstract] Fixed maturities - available for sale Payments to Acquire Debt Securities, Available-for-sale Equity securities - available for sale Payments to Acquire Available-for-sale Securities, Equity Mortgage loans Payments to Acquire Mortgage Notes Receivable Derivative instruments Payments for Derivative Instrument, Investing Activities Policy loans Payments to Fund Policy Loans Securities and indebtedness of related parties Payments to Acquire Equity Method Investments Other long-term investments Payments to Acquire Other Investments Short-term investments, net change Payments for (Proceeds from) Short-term Investments Purchases and disposals of property and equipment, net Payments for (Proceeds from) Productive Assets Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Financing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Contract holder account deposits Additions to Contract Holders Funds Contract holder account withdrawals Withdrawal from Contract Holders Funds Dividends paid Payments of Ordinary Dividends, Common Stock Proceeds from Issuance of Debt Proceeds from Issuance of Debt Repayments of Debt Repayments of Debt Issuance or repurchase of common stock, net Proceeds from (Repurchase of) Equity Proceeds from (Payments for) Other Financing Activities Proceeds from (Payments for) Other Financing Activities Net cash provided by (used in) financing activities Net Cash Provided by (Used in) Financing Activities Decrease in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents at beginning of period Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Supplemental disclosures of cash flow information Supplemental Cash Flow Information [Abstract] Interest Paid, Excluding Capitalized Interest, Operating Activities Interest Paid, Excluding Capitalized Interest, Operating Activities Cash (paid) received during the period for income taxes Income Taxes Paid, Net Stockholders' Equity Attributable to Parent [Abstract] Other Comprehensive Income Location [Axis] Other Comprehensive Income Location [Axis] Other Comprehensive Income Location [Domain] Other Comprehensive Income Location [Domain] reclassifications out of accumulated other comprehensive income reclassifications out of accumulated other comprehensive income [Member] Reclassifications out of accumulated other comprehensive income [Member] Accumulated Net Unrealized Investment Gain (Loss) AOCI, Accumulated Gain (Loss), Debt Securities, Available-for-sale, Parent [Member] Accumulated Other-than-Temporary Impairment Accumulated Other-than-Temporary Impairment Attributable to Parent [Member] Accumulated Defined Benefit Plans Adjustment Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member] Change in offsets to unrealized on investments Change in offsets to unrealized on investments Change in offsets to unrealized on investments, includes changes in amortization pattern of DAC, VIIF & URR and provision for deferred income tax. Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, before Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Pension and Other Postretirement Benefit Plans, before Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax Other Compreshensive Income (Loss), Reclassification Adjustment from AOCi, before Tax Other Comprehensive Income (Loss), before Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Pension and Other Postretirement Benefit Plans, Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, Tax Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Net of Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Net of Tax Other Comprehensive Income (Loss), Reclassification, Pension and Other Postretirement Benefit Plans, Net Gain (Loss) Recognized in Net Periodic Benefit Cost, Net of Tax Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, after Tax Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI, Net of Tax, Attributable to Parent Comprehensive Income (Loss), Net of Tax, Attributable to Parent Schedule of Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table] Schedule of Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Line Items] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Roll Forward] Balance at beginning of period Other than Temporary Impairment, Credit Losses Recognized in Earnings, Credit Losses on Debt Securities Held Reductions due to securities sold Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Securities Sold Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Change in Status Other than Temporary Impairment, Credit Losses Recognized in Earnings, Reductions, Change in Status Balance at end of period Stockholders' Equity Note [Abstract] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Common Stock Common Stock [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common Class A Common Class A [Member] Common Class B Common Class B [Member] Class of Stock [Line Items] Class of Stock [Line Items] Shares of common stock repurchased Stock Repurchased During Period, Shares Purchase of common stock Stock Repurchased During Period, Value Stock Repurchase Program, Remaining Authorized Repurchase Amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Common stock, without par value Common Stock, Value, Outstanding Stock Issued During Period, Shares, Stock-based Compensation, Net of Forfeitures Shares Issued, Shares, Share-based Payment Arrangement, after Forfeiture Stock-based compensation Shares Issued, Value, Share-based Payment Arrangement, after Forfeiture Accounting Changes and Error Corrections [Abstract] Basis of Accounting, Policy [Policy Text Block] Basis of Accounting, Policy [Policy Text Block] Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Variable Interest Entities [Axis] Variable Interest Entities [Axis] Variable Interest Entity, Classification [Domain] Variable Interest Entity, Classification [Domain] Low income housing tax credits Low income housing tax credits [Member] Investments in low income housing tax credits, as part of our equity method investments [Member] Investment companies Investment companies [Member] Investment in investment companies, as part of our equity method investments. Real estate limited partnerships Real estate limited partnerships [Member] Investments in real estate limited partnerships, as part of our equity method investments [Member] Other VIE investments Other VIE investments [Member] Investments in other VIE investments, as part of our equity method investments [Member] Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets Variable Interest Entity, Nonconsolidated, Carrying Amount, Assets Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount Variable Interest Entity, Reporting Entity Involvement, Maximum Loss Exposure, Amount Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] AOCI Attributable to Parent AOCI Attributable to Parent [Member] Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Reclassification Adjustments, Net of Tax Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, before Reclassification Adjustments, after Tax Other Comprehensive (Income) Loss, Pension and Other Postretirement Benefit Plans, Adjustment, before Reclassification Adjustments, Net of Tax Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax Other Comprehensive (Income) Loss, Reclassification Adjustment from AOCI for Write-down of Securities, Net of Tax Investment Operations Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Fair Values Derivatives, Balance Sheet Location, by Derivative Contract Type [Table] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Other Investments Other Investments [Member] Reinsurance Recoverable Including Reinsurance Premium Paid Reinsurance Recoverable Including Reinsurance Premium Paid [Member] Available-for-sale Securities Contract Holder Funds Contract Holder Funds [Member] Other Liabilities Other Liabilities [Member] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Investment Income Investment Income [Member] Insurance sensitive product charges Insurance sensitive product charges [Member] Insurance sensitive product charges [Member] Derivative Instrument Risk [Axis] Derivative Instrument [Axis] Derivative Contract Type [Domain] Derivative Contract [Domain] Equity Option Equity Option [Member] Embedded Derivative Financial Instruments - MODCO Embedded Derivative Financial Instruments - MODCO [Member] Embedded Derivative Financial Instruments - MODCO [Member] Embedded Derivative Financial Instruments - Interest only Security Embedded Derivative Financial Instruments - Interest only Security [Member] Embedded Derivative Financial Instruments - Interest only Security [Member] Embedded Derivative Financial Instruments Embedded Derivative Financial Instruments [Member] Derivatives, Fair Value [Line Items] Derivatives, Fair Value [Line Items] Derivative assets Derivative Asset Derivative Asset, Assumed Derivative Asset, Assumed Derivative Asset, Assumed Derivative Liabilities Derivative Liability Derivative, Gain (Loss) on Derivative, Net Derivative, Gain (Loss) on Derivative, Net Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset Net Derivative Exposure Net Derivative Exposure Net Derivative Exposure Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Private Equity Funds, US Private Equity Funds, US [Member] Corporate Fair Value, Inputs, Level 1 Fair Value, Inputs, Level 1 [Member] Fair Value, Inputs, Level 2 Fair Value, Inputs, Level 2 [Member] Fair Value Measured at Net Asset Value Per Share Fair Value Measured at Net Asset Value Per Share [Member] Reported Value Measurement Reported Value Measurement [Member] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Mortgage-backed securities available-for-sale Mortgage-backed Securities Available-for-sale, Fair Value Disclosure Other investments Cash and short-term investments Cash and short-term investments, fair value disclosure Cash and short-term investments, fair value disclosure Reinsurance recoverable Embedded Derivative, Fair Value of Embedded Derivative Asset Assets held in separate accounts Separate Account Asset Future policy benefits - index product embedded derivatives Liabilities Related to Investment Contracts, Fair Value Disclosure Other liabilities Other Liabilities, Fair Value Disclosure Total liabilities Financial and Nonfinancial Liabilities, Fair Value Disclosure Investments Net Asset Value Alternative Investment Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments Consolidated Balance Sheets [Abstract] Consolidated Balance Sheets [Abstract] Preferred Stock Preferred Stock [Member] Available-for-sale Securities, Debt Maturities, Amortized Cost Basis Debt Securities, Available-for-sale, Amortized Cost Equity Securities, Cost Equity Securities, Cost Equity Securities, Cost Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Preferred Stock, Shares Issued Preferred Stock, Shares Issued Preferred Stock, Shares Outstanding Preferred Stock, Shares Outstanding Common Stock, Shares Authorized Common Stock, Shares Authorized Common Stock, Shares, Issued Common Stock, Shares, Issued Fair Value Fair Value Disclosures [Text Block] Valuation of our Financial Instruments Measured on Recurring Basis by hierarchy levels [Table Text Block] Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Level 3 fixed maturities on Measurement on Recurring Basis by Valuation Technique [Table Text Block] Fair Value Measurement Inputs and Valuation Techniques [Table Text Block] Quantitative Information about Level 3 Fair Value Measurement Inputs [Text Block] Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Level 3 Financial Instruments Changes in Fair Value [Table Text Block] Level 3 Financial Instruments Changes in Fair Value [Table Text Block] Level 3 Financial Instruments Changes in Fair Value, rollforward of balances with purchases, disposals, transfers in/out, realized and unrealized gains/losses. [Table Text Block] Financial Instruments Not Reported at Value [Table Text Block] Financial Instruments Not Reported at Value [Table Text Block] Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined) that are not measured at fair value on a recurring basis. Such disclosures about the financial instruments include the fair value of the required items together with their carrying amounts (as appropriate). The fair value measurements at the reporting date also include the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Schedule of Segment Reporting Infomation by Segment [Abstract] Schedule of Segment Reporting Infomation by Segment [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Pre-Tax on Equity Income (Loss) Pre-Tax on Equity Income (Loss) Pre-Tax on Equity Income (Loss) Income Tax on Equity Income Income Tax on Equity Income Income Tax on Equity Income Income (Loss) from Equity Method Investments SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Schedule [Table] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Schedule [Table] Real Estate, Type of Property [Axis] Real Estate, Type of Property [Axis] Real Estate, Property Type [Domain] Real Estate [Domain] Office Office Building [Member] Retail Retail Site [Member] Industrial Industrial Property [Member] Other property type Other Property [Member] Geographical [Axis] Geographical [Axis] Geographical [Domain] Geographical [Domain] South Atlantic South Atlantic [Member] Represents the South Atlantic region of the United States. Pacific Pacific [Member] Represents the Pacific region of the United States. East North Central East North Central [Member] Represents the East North Central region of the United States. West North Central West North Central [Member] Represents the West North Central region of the United States. Mountain Mountain [Member] Represents the Mountain region of the United States. West South Central West South Central [Member] Represents the West South Central region of the United States. East South Central East South Central [Member] East South Central [Member] Middle Atlantic Middle Atlantic [Member] Middle Atlantic [Member] New England New England [Member] New England [Member] Loan-to-Value Ratio [Axis] Loan-to-Value Ratio [Axis] Loan-to-Value Ratio for mortgage loan credit quality [Axis] Total loan-to-value [Domain] Total loan-to-value [Domain] Total loan-to-value [Domain] 0% to 50% loan to value 0% to 50% loan to value [Member] 0% to 50% loan-to-value ratio [Member] 51% to 60% loan-to-value 51% to 60% loan-to-value [Member] 51% to 60% loan-to-value ratio [Member] 61% to 70% loan-to-value 61% to 70% loan-to-value [Member] 61% to 70% loan-to-value ratio [Member] 71% to 80% loan-to-value 71% to 80% loan-to-value [Member] 71% to 80% loan-to-value ratio [Member] 81% to 90% loan to value 81% to 90% loan to value [Member] 81% to 90% loan to value ratio [Member] MortgageLoans by Year of Origination [Axis] MortgageLoans by Year of Origination [Axis] MortgageLoans by Year of Origination [Axis] Mortgage Loans by Year of Origination [Domain] Mortgage Loans by Year of Origination [Domain] Mortgage Loans by Year of Origination [Domain] Year of origination 2019 Year of origination 2019 [Member] Year of origination 2019 [Member] Year of origination 2018 Year of origination 2018 [Member] Year of origination 2018 [Member] Year of origination 2017 Year of origination 2017 [Member] Year of origination 2017 [Member] Year of origination 2016 Year of origination 2016 [Member] Year of origination 2016 [Member] Year of origination 2015 Year of origination 2015 [Member] Year of origination 2015 Year of origination prior Year of origination prior [Member] Year of origination prior [Member] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items] Carrying Value SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate Percentage of Mortgage Loans Percentage of Mortgage Loans Represents amount as a percentage of the total amortized cost of mortgage loans. Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity Note Disclosure [Text Block] Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Schedule of Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Table] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items] Numerator [Abstract] Numerator [Abstract] Numerator [Abstract] Net income attributable to FBL Financial Group, Inc. Less: Dividends Series B preferred stock Dividends, Preferred Stock, Cash Income available to common stockholders Net Income (Loss) Available to Common Stockholders, Basic Denominator [Abstract] Denominator [Abstract] Denominator [Abstract] Weighted average shares - diluted Weighted Average Number of Shares Outstanding, Diluted Weighted average shares - basic Weighted Average Number of Shares Outstanding, Basic Effect of dilutive securities - stock-based compensation Weighted Average Number Diluted Shares Outstanding Adjustment Lessee Disclosure [Abstract] Operating Leases [Table] Operating Leases [Table] Operating Leases [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Majority Shareholder Majority Shareholder [Member] Operating Leases [Line Items] Operating Leases [Line Items] [Line Items] for Operating Leases [Table] Lessee, Operating Lease, at Carrying Value Lessee, Operating Lease, at Carrying Value Lessee, Operating Lease, at Carrying Value Lessee, Operating Lease, Discount Rate Lessee, Operating Lease, Discount Rate Operating Lease, Expense Operating Lease, Expense Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Two Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Three Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Four Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due after Year Five Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Liability, Payments, Due Lessee, Operating Lease, Future Value of Interest Expense Lessee, Operating Lease, Future Value of Interest Expense Lessee, Operating Lease, Future Value of Interest Expense Leases [Abstract] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Lessee, Operating Lease, Liability, Maturity [Table Text Block] Segment Reporting [Abstract] Reconciliation of Revenue from Segments to Consolidated [Table] Reconciliation of Revenue from Segments to Consolidated [Table] Segment Reporting, Revenue Reconciling Item [Line Items] Segment Reporting, Revenue Reconciling Item [Line Items] Pre-Tax Operating Income (Loss) Pre-Tax Operating Income (Loss) Pre-Tax Operating Income (Loss) Realized gains losses on investments net of offsets Realized gains losses on investments net of offsets Realized gains losses on investments net of offsets, not included in operating income as they can fluctuate greatly from quarter to quarter. Derivatives unrealized gain net of offsets Derivatives unrealized gain net of offsets Derivatives change in net unrealized gain net of offsets, reconciling item from net income to operating income due to fluctuations from quarter to quarter. Net Income (Loss) Attributable to Parent Pre-tax Net Income (Loss) Attributable to Parent Pre-tax Net Income (Loss) Attributable to Parent Operating Income (Loss) Operating Income (Loss) Operating revenues Operating revenues Operating revenues, not net of expenses. Realized gains on investments related to revenue Realized gains on investments related to revenue Realized gains on investments, including only the offset for unearned revenue reserve as other offsets do not impact revenue. Derivative unrealized related to revenues Derivative unrealized related to revenues Derivative change in net unrealized related to revenues. Adjustment between Net income and Operating income. Includes only items included in revenues. Revenues Available-for-sale Securities, Debt Maturities [Abstract] Available-for-sale Securities, Debt Maturities [Abstract] Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract] Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract] Due in one year or less, amortized cost basis Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost Due after one year through five years, amortized cost basis Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost Due after five years through ten years, amortized cost basis Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost Due after ten years, amortized cost basis Debt Securities, Available-for-sale, Allocated and Single Maturity Date, Maturity, after 10 Years, Amortized Cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Amortized Cost Mortgage-backed and other asset-backed, amortized cost basis Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Amortized Cost Total fixed maturities, amortized cost basis Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract] Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract] Due in one year or less, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value Due after one year through five years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value Due after five years through ten years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value Due after ten years, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, after 10 Years, Fair Value Total fixed maturities with maturity date, fair value Debt Securities, Available-for-sale, Maturity, Allocated and Single Maturity Date, Fair Value Mortgage-backed and other asset-backed, fair value Debt Securities, Available-for-sale, Maturity, without Single Maturity Date, Fair Value Total fixed maturities, fair value Debt Securities, Available-for-sale Schedule of Impaired Financing Receivable [Table] Schedule of Impaired Financing Receivable [Table] Credit Quality Indicator [Axis] Internal Credit Assessment [Axis] Financing Receivable, by Credit Quality Indicator [Domain] Internal Credit Assessment [Domain] Financing Receivable, Impaired [Line Items] Financing Receivable, Impaired [Line Items] Impaired Financing Receivable, Unpaid Principal Balance Impaired Financing Receivable, Unpaid Principal Balance Financing Receivable, Allowance for Credit Loss Impaired Financing Receivable, Recorded Investment Impaired Financing Receivable, Recorded Investment Debt Disclosure [Text Block] Debt Disclosure [Text Block] Statement of Comprehensive Income [Abstract] Change in net unrealized investment gains/losses Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Change in underfunded status of postretirement benefit plans Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax Total other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Total comprehensive income (loss), net of tax Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Comprehensive (income) loss attributable to noncontrolling interest Total comprehensive income (loss) applicable to FBL Financial Group, Inc. Amortized Cost Available-for-sale Securities, Amortized Cost Basis Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Non-credit losses on other-than-temporary impairments Other than Temporary Impairment Losses, Investments Portion in Other Comprehensive Income, Before Tax, Including Portion Attributable to Noncontrolling Interest, Available-for-sale Securities The amount of other than temporary impairment loss on an available-for-sale debt security related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount, which includes the portion attributable to the noncontrolling interest, if any, is a portion of the deduction from the total impairment losses of investments (before taxes) presented on the income statement; this amount is also referred to as the amount incurred by the reporting entity or the consolidated entity. Significant Accounting Policies [Abstract] Significant Accounting Policies [Abstract] Significant Accounting Policies Significant Accounting Policies [Text Block] Statement of Financial Position [Abstract] Class A common stock, without par value - authorized 88,500,000 shares, issued and outstanding 24,650,895 shares in 2019 and 24,707,402 shares in 2018 Class B common stock, without par value - authorized 1,500,000 shares, issued and outstanding 11,413 shares in 2019 and 2018 Assets Assets [Abstract] Investments: Investments [Abstract] Fixed maturities - available for sale, at fair value (amortized cost: 2019 - $6,956,353; 2018 - $6,856,277) Equity securities at fair value (cost: 2019 - $93,365; 2018 - $93,564) Equity Securities Equity Securities Mortgage loans Mortgage Loans on Real Estate, Commercial and Consumer, Net Real estate Real Estate Investments, Net Policy loans Loans, Gross, Insurance Policy Short-term investments Short-term Investments Other investments Other Investments Total investments Investments Cash and cash equivalents Securities and indebtedness of related parties Equity Method Investments Accrued investment income Accrued Investment Income Receivable Amounts receivable from affiliates Accounts Receivable, Related Parties, Current Reinsurance recoverable Reinsurance Recoverables, Including Reinsurance Premium Paid Deferred acquisition costs Deferred Policy Acquisition Cost Value of insurance in force acquired Present Value of Future Insurance Profits, Net Current income taxes recoverable Income Taxes Receivable, Current Other assets Other Assets Total assets Assets Liabilities and stockholders' equity Liabilities and Equity [Abstract] Liabilities: Liabilities [Abstract] Policy liabilities and accruals: Liability for Future Policy Benefits and Unpaid Claims and Claims Adjustment Expense [Abstract] Future policy benefits: Liability for Future Policy Benefit, before Reinsurance [Abstract] Interest sensitive products Interest sensitive products The accrued obligation to policyholders at the balance sheet date that relates to universal life and variable universal life insurance policies; individual and group annuities (including fixed rate, index and variable); and supplemental contracts involving life contingencies. Traditional life insurance and accident and health products Liability for Future Policy Benefits, Life Other policy claims and benefits Other policy claims and benefits Amounts payable for death benefits net of reinsurance. Also includes an unearned revenue reserve that relect the unamortized balance of charges assessed to interest sensitive contracts to compensate us for services to be performed over future periods. Supplementary contracts without life contingencies Deposit Contracts, Liabilities Advance premiums and other deposits Other Policyholder Funds Amounts payable to affiliates Accounts Payable, Related Parties, Current Short-term debt payable to non-affiliates Long-term debt payable to non-affiliates Long-term Debt Deferred income taxes Deferred Tax Liabilities, Net Other liabilities Other Liabilities Liabilities related to separate accounts Separate Account, Liability Total liabilities Liabilities Stockholders' equity: Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] FBL Financial Group, Inc. stockholders' equity: Preferred stock, without par value, at liquidation value - authorized 10,000,000 shares, issued and outstanding 5,000,000 Series B shares Preferred Stock, Value, Outstanding Retained earnings Retained Earnings (Accumulated Deficit) Total FBL Financial Group, Inc. stockholders’ equity Stockholders' Equity Attributable to Parent Noncontrolling interest Stockholders' Equity Attributable to Noncontrolling Interest Total stockholders’ equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total liabilities and stockholders’ equity Liabilities and Equity Statement of Stockholders' Equity [Abstract] Series B Preferred Stock Class A and Class B Common Stock Accumulated Other Comprehensive Income Non- controlling Interest Noncontrolling Interest [Member] Balance Other comprehensive loss Purchase of common stock Dividends on preferred stock Dividends on common stock Dividends, Common Stock, Cash Noncontrolling Interest, Period Increase (Decrease) Noncontrolling Interest, Period Increase (Decrease) Balance Statistical Measurement [Axis] Statistical Measurement [Axis] Statistical Measurement [Domain] Statistical Measurement [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Weighted Average Weighted Average [Member] Valuation Approach and Technique [Axis] Valuation Approach and Technique [Axis] Valuation Approach and Technique [Domain] Valuation Approach and Technique [Domain] Valuation Technique, Discounted Cash Flow Valuation Technique, Discounted Cash Flow [Member] Measurement Input Type [Axis] Measurement Input Type [Axis] Measurement Input Type [Domain] Measurement Input Type [Domain] Measurement Input, Credit Spread Measurement Input, Credit Spread [Member] Measurement Input, Entity Credit Risk Measurement Input, Entity Credit Risk [Member] Measurement Input, Risk Margin Measurement Input, Risk Margin [Member] Measurement Input, Risk Margin [Member] Asset Class [Axis] Asset Class [Axis] Fair Value by Asset Class [Domain] Asset Class [Domain] Commercial mortgage-backed Mortgage-backed Securities, Issued by Private Enterprises [Member] Collateralized Mortgage Backed Securities Collateralized Mortgage Backed Securities [Member] Asset fair value by technique Asset fair value by technique [Member] Asset fair value by technique - level 3 assets not including those for which fair value was based on non-binding broker quotes where we could not reasonably obtain the quantitative unobservable inputs. [Member] Input range and weighted average Input range and weighted average Input range and weighted average of unobservable inputes to fair value measurements Defined Benefit Plan Pension and Other Postretirement Benefits Disclosure [Text Block] Schedule of Financial Instruments Not Reported at Fair Value [Table] Schedule of Financial Instruments Not Reported at Fair Value [Table] Schedule of Financial Instruments Not Reported at Fair Value [Table] Portion at Other than Fair Value Measurement Portion at Other than Fair Value Measurement [Member] Financial Instruments Not Reported at Fair Value [Line Items] Financial Instruments Not Reported at Fair Value [Line Items] Financial Instruments Not Reported at Fair Value [Line Items] Mortgage loans Total assets Assets not measured at fair value Assets not measured at fair value Future policy benefits Supplemental contracts without life contingencies, fair value disclosure Supplemental contracts without life contingencies, fair value disclosure Supplemental contracts without life contingencies, fair value disclosure Deposit Contracts, Liabilities Advance premiums and other deposits Advance premiums and other deposits, fair value disclosure Advance premiums and other deposits, fair value disclosure Short term debt, fair value disclosure Short term debt, fair value disclosure Short term debt, fair value disclosure Long-term debt Long-term Debt, Fair Value Total liabilities Liabilities not measured at fair value Liabilities not measured at fair value Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entities [Table] Entities [Table] Entity Information [Line Items] Entity Information [Line Items] Document Type Document Type Document Quarterly Report Document Quarterly Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Current Reporting Status Entity Current Reporting Status Entity Interactive Data Current Entity Interactive Data Current Entity Filer Category Entity Filer Category Entity Small Business Entity Small Business Entity Emerging Growth Company Entity Emerging Growth Company Entity Shell Company Entity Shell Company Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Available-for-sale Securities [Table Text Block] Available-for-sale Securities [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Unrealized Gain (Loss) on Investments [Table Text Block] Unrealized Gain (Loss) on Investments [Table Text Block] Schedule of Unrealized Loss on Investments [Table Text Block] Schedule of Unrealized Loss on Investments [Table Text Block] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table Text Block] Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table Text Block] Realized Gain (Loss) on Investments [Table Text Block] Realized Gain (Loss) on Investments [Table Text Block] Mortgage Loans by Colateral Type [Table Text Block] Mortgage Loans by Colateral Type [Table Text Block] Mortgage Loans by Colateral Type [Table Text Block] Mortgage Loans by Geograpic Location [Table Text Block] Mortgage Loans by Geograpic Location [Table Text Block] Mortgage Loans by Geograpic Location [Table Text Block] Mortgage Loans by loan to value ratio [Table Text Block] Mortgage Loans by loan to value ratio [Table Text Block] Mortgage Loans by loan to value ratio [Table Text Block] Mortgage loans by year of origination [Table Text Block] Mortgage loans by year of origination [Table Text Block] Mortgage loans by year of origination [Table Text Block] Impaired Financing Receivables [Table Text Block] Impaired Financing Receivables [Table Text Block] Financing Receivable, Allowance for Credit Loss [Table Text Block] Financing Receivable, Allowance for Credit Loss [Table Text Block] Schedule of Variable Interest Entities [Table Text Block] Schedule of Variable Interest Entities [Table Text Block] Schedule of Derivative Instruments [Table Text Block] Schedule of Derivative Instruments [Table Text Block] Dividends Declared [Table Text Block] Dividends Declared [Table Text Block] Schedule of Stock by Class [Table Text Block] Schedule of Stock by Class [Table Text Block] Schedule of Comprehensive Income (Loss) [Table Text Block] Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Reclassification out of Accumulated Other Comprehensive Income [Table Text Block] Dividends [Abstract] Regular quarterly cash dividend Regular quarterly cash dividend [Member] Regular quarterly cash dividend [Member] Special cash dividend Special cash dividend [Member] Special cash dividend [Member] Cash dividends per common share Common Stock, Dividends, Per Share, Cash Paid Cash dividends per preferred share Preferred Stock, Dividends, Per Share, Cash Paid Payment Of Special Cash Dividend Payment Of Special Cash Dividend Payment Of Special Cash Dividend