Document and entity information Document - USD ($)	12 Months Ended
	Dec. 31, 2016	Feb. 27, 2017
Document Information [Line Items]
Entity Registrant Name	FBL FINANCIAL GROUP INC
Entity Central Index Key	0001012771
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float	$ 595,276,142
Common Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		24,904,888
Common Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		11,413