Annual report pursuant to Section 13 and 15(d)


Cover - USD ($)
12 Months Ended
Dec. 31, 2022
Mar. 27, 2023
Jul. 01, 2022
Cover [Abstract]      
Document Type 10-K/A    
Amendment Flag true    
Amendment Description On March 31, 2023, Williams Industrial Services Group Inc. ("Williams," the "Company," "we," "us," or "our") filed its Annual Report on Form 10-K for the fiscal year ended December 31, 2022 (the "Original Form 10-K") with the U.S. Securities and Exchange Commission (the "SEC"). We are filing this Annual Report on Form 10-K/A (this "Amendment") as Amendment No. 1 to the Original Form 10-K for the purposes of amending Part III, Items 10, 11, 12, 13 and 14 of the Original Form 10-K to include the information required by such Items. This information was previously omitted from the Original Form 10-K in reliance on General Instruction G(3) to Form 10-K. This Amendment amends and restates in their entirety Items 10, 11, 12, 13 and 14 of Part III of the Original Form 10-K.    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Dec. 31, 2022    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2022    
Current Fiscal Year End Date --12-31    
Entity File Number 001-16501    
Entity Registrant Name Williams Industrial Services Group Inc.    
Entity Central Index Key 0001136294    
Entity Tax Identification Number 73-1541378    
Entity Incorporation, State or Country Code DE    
Entity Address, Address Line One 200 Ashford Center North    
Entity Address, Address Line Two Suite 425     
Entity Address, City or Town Atlanta    
Entity Address, State or Province GA    
Entity Address, Postal Zip Code 30338    
City Area Code 770    
Local Phone Number 879-4400    
Title of 12(b) Security Common Stock, par value $0.01 per share    
Trading Symbol WLMS    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Non-accelerated Filer    
Entity Small Business true    
Entity Emerging Growth Company false    
Entity Shell Company false    
Entity Public Float     $ 23,197,687
Entity Common Stock, Shares Outstanding   27,058,317  
ICFR Auditor Attestation Flag false    
Auditor Name Moss Adams LLP    
Auditor Location Dallas, Texas    
Auditor Firm ID 659