v3.26.1
Document and Entity Information - shares
 6 Months Ended
Jun. 30, 2026
Aug. 06, 2026
Document and Entity Information    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Jun. 30, 2026  
Document Transition Report false  
Entity Registrant Name SPRING VALLEY ACQUISITION CORP. IV  
Entity Incorporation, State or Country Code E9  
Entity File Number 001-43110  
Entity Tax Identification Number 00-0000000  
Entity Address, Address Line One 4030 Maple Avenue  
Entity Address, Adress Line Two Suite 500  
Entity Address, City or Town Dallas  
Entity Address State Or Province TX  
Entity Address, Postal Zip Code 75219  
City Area Code 214  
Local Phone Number 308-5230  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company true  
Entity Central Index Key 0002098242  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q2  
Amendment Flag false  
Units    
Document and Entity Information    
Title of 12(b) Security Units, each consisting of one Class A ordinary share and one-fourth of one redeemable warrant  
Trading Symbol SVIVU  
Security Exchange Name NASDAQ  
Class ordinary shares    
Document and Entity Information    
Title of 12(b) Security Class A ordinary shares, par value $0.0001 per share  
Trading Symbol SVIV  
Security Exchange Name NASDAQ  
Class A ordinary shares    
Document and Entity Information    
Entity Common Stock, Shares Outstanding   23,000,000
Class B ordinary shares    
Document and Entity Information    
Entity Common Stock, Shares Outstanding   7,666,667
Warrant    
Document and Entity Information    
Title of 12(b) Security Warrants, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50  
Trading Symbol SVIVW  
Security Exchange Name NASDAQ