v3.10.0.1
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2018
Oct. 26, 2018
Document and Entity Information [Abstract]    
Entity Registrant Name OMNICELL, Inc  
Entity Central Index Key 0000926326  
Document Type 10-Q  
Document Period End Date Sep. 30, 2018  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock, Shares Outstanding   39,626,231
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Entity Emerging Growth Company false  
Entity Small Business false