XML 27 R1.htm IDEA: XBRL DOCUMENT v3.19.1
Document and Entity Information - USD ($)
$ in Billions
 12 Months Ended
Dec. 31, 2018
Mar. 01, 2019
Jun. 30, 2018
Document And Entity Information [Abstract]      
Entity registrant name MOSAIC CO    
Trading Symbol MOS    
Document type 10-K    
Entity central index key 0001285785    
Amendment flag false    
Entity current reporting status Yes    
Entity voluntary filers No    
Document Fiscal Year Focus 2018    
Document Fiscal Period Focus FY    
Document period end date Dec. 31, 2018    
Current Fiscal Year End Date --12-31    
Entity filer category Large Accelerated Filer    
Entity well known seasoned issuer Yes    
Entity Shell Company false    
Entity Emerging Growth Company false    
Entity Small Business false    
Entity common stock shares outstanding   385,470,499  
Entity public float     $ 10.9