v3.25.1
Document And Entity Information - shares
 3 Months Ended
Mar. 31, 2025
May 05, 2025
Entity Information [Line Items]    
Entity Registrant Name NextNav Inc.  
Document Type 10-Q  
Amendment Flag false  
Entity Central Index Key 0001865631  
Document Period End Date Mar. 31, 2025  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2025  
Document Fiscal Period Focus Q1  
Document Quarterly Report true  
Document Transition Report false  
Entity File Number 001-40985  
Entity Incorporation, State or Country Code DE  
Entity Tax Identification Number 87-0854654  
Entity Address, Address Line One 11911 Freedom Dr.  
Entity Address, Address Line Two Ste. 200  
Entity Address, City or Town Reston  
Entity Address, State or Province VA  
Entity Address, Postal Zip Code 20190  
City Area Code 800  
Local Phone Number 775-0982  
Title of 12(b) Security Common Stock, par value $0.0001 per share  
Trading Symbol NN  
Security Exchange Name NASDAQ  
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  
Entity Common Stock, Shares Outstanding   132,397,178