Document And Entity Information (USD $)
9 Months Ended
Sep. 30, 2011
Oct. 26, 2011
Jun. 30, 2010
Entity Registrant NameCOMPASS MINERALS INTERNATIONAL INC  
Entity Central Index Key0001227654  
Current Fiscal Year End Date--12-31  
Entity Well-known Seasoned IssuerYes  
Entity Voluntary FilersNo  
Entity Current Reporting StatusYes  
Entity Filer CategoryLarge Accelerated Filer  
Entity Public Float  $ 2,301,535,835
Entity Common Stock, Shares Outstanding 32,915,041 
Document Fiscal Year Focus2011  
Document Fiscal Period FocusQ3  
Document Type10-Q  
Amendment Flagfalse  
Document Period End DateSep. 30, 2011