Quarterly report pursuant to Section 13 or 15(d)

Cover Page

v3.21.2
Cover Page - shares
 9 Months Ended
Sep. 30, 2021
Nov. 08, 2021
Document Information [Line Items]    
Document Type 10-Q  
Document Quarterly Report true  
Document Period End Date Sep. 30, 2021  
Document Transition Report false  
Entity File Number 001-39644  
Entity Registrant Name Archaea Energy Inc.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 85-2867266  
Entity Address, Address Line One 4444 Westheimer Road  
Entity Address, Address Line Two Suite G450  
Entity Address, City or Town Houston  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 77027  
City Area Code 346  
Local Phone Number 708-8272  
Entity Information, Former Legal or Registered Name Rice Acquisition Corp.  
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 false  
Amendment Flag false  
Document Fiscal Period Focus Q3  
Document Fiscal Year Focus 2021  
Current Fiscal Year End Date --12-31  
Entity Central Index Key 0001823766  
Common Stock    
Document Information [Line Items]    
Title of 12(b) Security Class A Common Stock, par value $0.0001 per share  
Trading Symbol LFG  
Security Exchange Name NYSE  
Class A Units    
Document Information [Line Items]    
Title of 12(b) Security Warrants, each exercisable for one share of Class A Common Stock at a price of $11.50 per share  
Trading Symbol LFG WS  
Security Exchange Name NYSE  
Entity Common Stock, Shares Outstanding   53,590,976
Class B Units    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   62,281,735
Former Address    
Document Information [Line Items]    
Entity Address, Address Line One 102 East Main Street  
Entity Address, Address Line Two Second Story  
Entity Address, City or Town Carnegie  
Entity Address, State or Province PA  
Entity Address, Postal Zip Code 15106