Segment Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Revenues	$ 184,179	$ 181,284	$ 181,285	$ 179,666	$ 182,624	$ 175,494	$ 186,745	$ 177,946	$ 726,414	$ 722,809	$ 692,939
Operating revenues									721,635	715,018	687,732
Realized gains on investments related to revenue									(1,771)	10,482	2,937
Derivative unrealized related to revenues									6,550	(2,691)	2,270
Net investment income	101,549	103,514	100,722	98,385	99,005	95,882	97,489	98,773	404,170	391,149	382,082
Investment Income, Net									397,620	393,840	379,812
Investment Income, Nonoperating									6,550	(2,691)	2,270
Depreciation, Depletion and Amortization									28,437	31,818	28,945
Other Depreciation and Amortization									28,548	31,925	28,631
Deferred Policy Acquisition Cost, Amortization Expense, Net Investment Gains (Losses)									(673)	225	189
Deferred Policy Acquisition Cost, Amortization Expense, Unrealized Investment Gains (Losses)									(562)	332	(125)
Net income attributable to FBL Financial Group, Inc.	$ 26,880	$ 30,017	$ 24,380	$ 25,946	$ 30,905	$ 26,659	$ 32,372	$ 23,591	107,223	113,527	109,941
Operating Income (Loss)									106,451	104,888	107,041
Pre-Tax Operating Income (Loss)									136,550	134,764	139,442
Income tax on operating income									(30,099)	(29,876)	(32,401)
Realized gains losses on investments net of offsets									713	(8,498)	(1,786)
Derivatives unrealized gain net of offsets									(1,485)	(141)	(1,114)
Operating Income offsets due to Interest Sensitive Product Reserves									900	100	100
Annuity
Segment Reporting Information [Line Items]
Operating revenues									214,486	212,420	203,477
Investment Income, Net									210,679	209,896	201,550
Other Depreciation and Amortization									8,253	4,548	5,709
Operating Income (Loss)									66,025	69,950	65,056
Life Insurance
Segment Reporting Information [Line Items]
Operating revenues									414,446	408,966	390,609
Investment Income, Net									154,427	152,730	146,349
Other Depreciation and Amortization									15,117	18,831	20,027
Operating Income (Loss)									55,977	53,146	51,521
Corporate and Other
Segment Reporting Information [Line Items]
Operating revenues									92,703	93,632	93,646
Investment Income, Net									32,514	31,214	31,913
Other Depreciation and Amortization									5,178	8,546	2,895
Operating Income (Loss)									$ 14,548	$ 11,668	$ 22,865