v3.26.3
Cover - shares
 9 Months Ended
Sep. 30, 2026
Nov. 02, 2026
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2026  
Document Transition Report false  
Entity File Number 001-38090  
Entity Registrant Name SOLARIS ENERGY INFRASTRUCTURE, INC.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 81-5223109  
Entity Address, Address Line One 9651 Katy Freeway, Suite 300  
Entity Address, City or Town Houston  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 77024  
City Area Code 281  
Local Phone Number 501-3070  
Title of 12(b) Security Class A Common Stock, $0.01 par value  
Trading Symbol SEI  
Security Exchange Name NYSE  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Central Index Key 0001697500  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Class A Common Stock    
Document and Entity Information    
Entity Common Stock, Shares Outstanding   69,470,966
Class B Common Stock    
Document and Entity Information    
Entity Common Stock, Shares Outstanding   10,697,246