Document and Entity Information (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Jun. 30, 2012	Feb. 12, 2013 Common Class A	Feb. 12, 2013 Common Class B
Entity 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, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding			24,260	1,141
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float (only reported at year end)		$ 296,609