Significant Accounting Policies Other income other expense (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Future policy benefits:
Future policy benefits, assumptions, average rate in investment yields in gross margin estimation	5.23%	5.48%	5.47%
Other Policyholder Claims and Benefits
Premiums from policies subject to participation in dividends	25.00%	28.00%	29.00%
Contracts in force subject to participation in dividends	9.00%	10.00%	10.00%
Other Income and Expenses [Abstract]
Real Estate Owned, Valuation Allowance	$ 0.0	$ 0.0
Farm Bureau Property & Casualty insurance company
Other Income and Expenses [Abstract]
Lease income	5.3	4.9	$ 4.6
Subsidiaries
Other Income and Expenses [Abstract]
Nonoperating Income (Expense)	1.7	2.7	2.5
Investment Advice [Member] \| Farm Bureau Property & Casualty insurance company
Other Income and Expenses [Abstract]
Revenue from Contract with Customer, Excluding Assessed Tax	$ 3.1	$ 2.9	$ 2.7
Minimum \| Participating Life Insurance Contract [Member]
Future policy benefits:
Future Policy Benefits, Interest Rate Assumptions	2.00%
Minimum \| Interest Sensitive Life [Member]
Future policy benefits:
Future Policy Benefits, Interest Rate Assumptions	1.00%	1.00%	1.00%
Maximum \| Participating Life Insurance Contract [Member]
Future policy benefits:
Future Policy Benefits, Interest Rate Assumptions	6.00%
Maximum \| Interest Sensitive Life [Member]
Future policy benefits:
Future Policy Benefits, Interest Rate Assumptions	5.50%	5.50%	5.50%

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Future policy benefits, assumptions, average rate in investment yields in gross margin estimation

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Premiums from policies subject to participation in dividends

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The assumed interest rate used to determine present value of future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and unpaid claim costs relating to insurance contracts including estimates of costs relating to incurred but not reported claims based on the estimated ultimate cost of settling the claims (including effects of inflation and other societal and economic factors), using past experience adjusted for current trends and any other factors that would modify past experience in the year the policy went into force.

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The total amount of revenue recognized for the period from operating leases, including minimum lease revenue, contingent revenue, percentage revenue and sublease revenue.

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For each period for which an income statement is required, disclosure of the changes in the allowance, including balances at end of period.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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