Document and Entity Information
3 Months Ended
Mar. 31, 2015
Apr. 30, 2015
Document and Entity Information    
Entity Registrant Name Hill International, Inc.  
Entity Central Index Key 0001287808  
Document Type 10-Q  
Document Period End Date Mar. 31, 2015  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Accelerated Filer  
Entity Common Stock, Shares Outstanding   50,373,822
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q1