v3.25.4
Document and Entity Information - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Feb. 10, 2026
Jun. 30, 2025
Entity Information [Line Items]      
Document Type 10-K    
Document Fiscal Period Focus FY    
Document Annual Report true    
Document Period End Date Dec. 31, 2025    
Document Transition Report false    
Amendment Flag false    
Document Fiscal Year Focus 2025    
Current Fiscal Year End Date --12-31    
Entity File Number 1-34907    
Entity Registrant Name STAG INDUSTRIAL, INC.    
Entity Central Index Key 0001479094    
Entity Incorporation, State or Country Code MD    
Entity Tax Identification Number 27-3099608    
Entity Address, Address Line One One Federal Street    
Entity Address, Address Line Two 23rd Floor    
Entity Address, City or Town Boston,    
Entity Address, State or Province MA    
Entity Address, Postal Zip Code 02110    
City Area Code 617    
Local Phone Number 574-4777    
Title of 12(b) Security Common Stock, $0.01 par value    
Trading Symbol STAG    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Entity Voluntary Filers No    
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    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 6,764
Entity Common Stock, Shares Outstanding   191,036,305  
Documents Incorporated by Reference [Text Block]
Portions of the registrant’s definitive Proxy Statement with respect to its 2026 Annual Meeting of Stockholders to be filed not later than 120 days after the end of the registrant’s fiscal year are incorporated by reference into Part II, Item 5 and Part III, Items 10, 11, 12, 13 and 14 hereof as noted therein.
    
Auditor Name PricewaterhouseCoopers LLP    
Auditor Location Boston, Massachusetts    
Auditor Firm ID 238    
Document Financial Statement Error Correction [Flag] false