v3.22.2.2
Cover Page - shares
 9 Months Ended
Sep. 30, 2022
Oct. 28, 2022
Cover [Abstract]    
Document Fiscal Year Focus 2022  
Document Type 10-Q  
Document Quarterly Report true  
Document Transition Report false  
Document Period End Date Sep. 30, 2022  
Entity File Number 001-36126  
Entity Registrant Name LGI HOMES, INC.  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 46-3088013  
Entity Address, Address Line One 1450 Lake Robbins Drive,  
Entity Address, Address Line Two Suite 430,  
Entity Address, City or Town The Woodlands,  
Entity Address, State or Province TX  
Entity Address, Postal Zip Code 77380  
City Area Code (281)  
Local Phone Number 362-8998  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Large Accelerated Filer  
Entity Small Business false  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   23,290,286
Title of 12(b) Security Common Stock, par value $0.01 per share  
Trading Symbol LGIH  
Security Exchange Name NASDAQ  
Entity Central Index Key 0001580670  
Current Fiscal Year End Date --12-31  
Document Fiscal Period Focus Q3  
Amendment Flag false