XML 11 R1.htm IDEA: XBRL DOCUMENT v3.24.1.u1
Cover - USD ($)
 12 Months Ended
Dec. 31, 2023
Mar. 22, 2024
Jun. 30, 2023
Document Type 10-K/A    
Amendment Flag false    
Document Annual Report true    
Document Transition Report false    
Document Period End Date Dec. 31, 2023    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2023    
Current Fiscal Year End Date --12-31    
Entity File Number 001-39281    
Entity Registrant Name TMC THE METALS COMPANY INC.    
Entity Central Index Key 0001798562    
Entity Tax Identification Number 00-0000000    
Entity Incorporation, State or Country Code A1    
Entity Address, Address Line One 595 Howe Street, 10th Floor    
Entity Address, City or Town Vancouver    
Entity Address, State or Province BC    
Entity Address, Postal Zip Code V6C 2T5    
City Area Code 574    
Local Phone Number 252-9333    
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 true    
Elected Not To Use the Extended Transition Period false    
Entity Shell Company false    
Entity Public Float     $ 274,979,313
Entity Common Stock, Shares Outstanding   318,249,878  
ICFR Auditor Attestation Flag false    
Document Financial Statement Error Correction [Flag] false    
Auditor Name Ernst & Young LLP    
Auditor Firm ID 1263    
Auditor Location Vancouver, Canada    
Common Shares, without par value      
Title of 12(b) Security Common Shares, without par value    
Trading Symbol TMC    
Security Exchange Name NASDAQ    
Redeemable warrants, each whole warrant exercisable for one Common Share, each at an exercise price of $11.50 per share      
Title of 12(b) Security Redeemable warrants, each whole warrant exercisable for one Common Share, each at an exercise price of $11.50 per share    
Trading Symbol TMCWW    
Security Exchange Name NASDAQ