Segment Information Segment assets & Text (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Segment assets		$ 10,005,572	$ 9,710,472
Unrealized Gains on assets in AOCI	[1]	474,634	123,158
Assets		10,480,206	9,833,630
Goodwill		9,900	9,900
Annuity
Segment Reporting Information [Line Items]
Segment assets		4,671,210	4,627,277
Goodwill		3,900	3,900
Life Insurance
Segment Reporting Information [Line Items]
Segment assets		3,665,179	3,528,561
Goodwill		6,100	6,100
Corporate and Other
Segment Reporting Information [Line Items]
Segment assets		1,669,183	1,554,634
Farm Bureau Property & Casualty insurance company
Segment Reporting Information [Line Items]
Operating Leases, Income Statement, Lease Revenue Depreciation and Amortization		$ 4,800	$ 4,500	$ 4,100

[1] Amounts are net adjustments for assumed changes in deferred acquisition costs and value of insurance in force acquired attributable to these items.