Quarterly report pursuant to Section 13 or 15(d)

Cover Page

v3.21.2
Cover Page - shares
6 Months Ended
Jun. 30, 2021
Aug. 19, 2021
Document Information [Line Items]    
Document Type 10-Q  
Amendment Flag false  
Document Period End Date Jun. 30, 2021  
Document Fiscal Year Focus 2021  
Document Fiscal Period Focus Q2  
Current Fiscal Year End Date --12-31  
Document Quarterly Report true  
Document Transition Report false  
Entity Registrant Name M3-Brigade Acquisition II Corp.  
Entity Central Index Key 0001839175  
Entity File Number 001-40162  
Entity Tax Identification Number 86-1359752  
Entity Interactive Data Current Yes  
Entity Current Reporting Status Yes  
Entity Incorporation, State or Country Code DE  
Entity Address, Address Line One 1700 Broadway, 19th Floor  
Entity Address, City or Town New York  
Entity Address, State or Province NY  
Entity Address, Postal Zip Code 10019  
City Area Code 212  
Local Phone Number 202-2200  
Entity Filer Category Non-accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company true  
Entity Ex Transition Period false  
Entity Shell Company true  
Capital Units [Member]    
Document Information [Line Items]    
Title of 12(b) Security Units, each consisting of one share of Class A Common Stock, $0.0001 par value per share, and one-third of one redeemable warrant  
Trading Symbol MBAC.U  
Security Exchange Name NYSE  
Class A Common Stock [Member]    
Document Information [Line Items]    
Title of 12(b) Security Class A common stock included as part of the units  
Trading Symbol MBAC  
Security Exchange Name NYSE  
Entity Common Stock, Shares Outstanding   40,000,000
Warrant [Member]    
Document Information [Line Items]    
Title of 12(b) Security Warrants included as part of the units, each whole warrant exercisable for one share of Class A common stock at an exercise price of $11.50  
Trading Symbol MBAC.WS  
Security Exchange Name NYSE  
Class B Common Stock [Member]    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   10,000,000