v3.26.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2026
May 06, 2026
Document Information [Line Items]    
Registrant Name THUNDER MOUNTAIN GOLD, INC.  
Registrant CIK 0000711034  
Fiscal Year End --12-31  
SEC Form 10-Q  
Period End date Mar. 31, 2026  
Tax Identification Number (TIN) 91-1031015  
Number of common stock shares outstanding   93,505,579
Filer Category Non-accelerated Filer  
Current with reporting Yes  
Interactive Data Current Yes  
Shell Company false  
Small Business true  
Emerging Growth Company false  
Document Quarterly Report true  
Document Transition Report false  
Entity File Number 001-08429  
Entity Incorporation, State or Country Code NV  
Entity Address, Address Line One 11770 W President Dr. STE F  
Entity Address, City or Town Boise  
Entity Address, State or Province ID  
Entity Address, Postal Zip Code 83713-8986  
City Area Code 208  
Local Phone Number 658-1037  
Title of 12(b) Security Common Stock, $0.001 par value  
Amendment Flag false  
Document Fiscal Year Focus 2026  
Document Fiscal Period Focus Q1