Annual report pursuant to Section 13 and 15(d)

Document And Entity Information

v3.8.0.1
Document And Entity Information - USD ($)
12 Months Ended
Dec. 31, 2017
Mar. 20, 2018
Jun. 30, 2016
Document And Entity Information [Abstract]      
Entity Registrant Name SEACOR Marine Holdings Inc.    
Entity Central Index Key 0001690334    
Current Fiscal Year End Date --12-31    
Entity Filer Category Non-accelerated Filer    
Document Type 10-K    
Document Period End Date Dec. 31, 2017    
Document Fiscal Year Focus 2017    
Document Fiscal Period Focus FY    
Amendment Flag false    
Entity Common Stock, Shares Outstanding   17,683,356  
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Public Float     $ 332,370,118