XML 15 R1.htm IDEA: XBRL DOCUMENT v3.5.0.2
Document and Entity Information - USD ($)
 6 Months Ended
Jun. 30, 2016
Aug. 05, 2016
Document and Entity Information [Abstract]    
Entity Registrant Name FIRST MID ILLINOIS BANCSHARES INC  
Entity Central Index Key 0000700565  
Current Fiscal Year End Date --12-31  
Entity Filer Category Accelerated Filer  
Entity Well-known Seasoned Issuer No  
Entity Voluntary Filers No  
Entity Current Reporting Status Yes  
Entity Public Float $ 199,087,000  
Document Fiscal Year Focus 2016  
Document Fiscal Period Focus Q2  
Document Type 10-Q  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   9,843,652
Document Period End Date Jun. 30, 2016