Annual report pursuant to Section 13 and 15(d)

Cover Page

v3.20.4
Cover Page - USD ($)
 12 Months Ended
Dec. 31, 2020
Feb. 16, 2021
Jun. 30, 2020
Entity Information [Line Items]      
Document Type 10-K    
Document Annual Report true    
Document Period End Date Dec. 31, 2020    
Document Transition Report false    
Entity Central Index Key 0001234006    
Document Fiscal Year Focus 2020    
Document Fiscal Period Focus FY    
Current Fiscal Year End Date --12-31    
Amendment Flag false    
Entity File Number 001-33097    
Entity Registrant Name GLADSTONE COMMERCIAL CORP    
Entity Incorporation, State or Country Code MD    
Entity Tax Identification Number 02-0681276    
Entity Address, Address Line One 1521 Westbranch Drive,    
Entity Address, Address Line Two Suite 100    
Entity Address, City or Town McLean,    
Entity Address, State or Province VA    
Entity Address, Postal Zip Code 22102    
City Area Code 703    
Local Phone Number 287-5800    
Entity Well-known Seasoned Issuer No    
Entity Voluntary Filers No    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Entity Shell Company false    
Entity Public Float     $ 624,884,164
Entity Common Stock, Shares Outstanding   35,734,269  
Documents Incorporated by Reference Portions of the Registrant’s Proxy Statement, to be filed no later than April 30, 2021, relating to the Registrant’s 2021 Annual Meeting of Stockholders, are incorporated by reference into Part III of this Annual Report on Form 10-K.    
Common Stock      
Entity Information [Line Items]      
Title of 12(b) Security Common Stock, par value $0.001 per share    
Trading Symbol GOOD    
Security Exchange Name NASDAQ    
7.00% Series D Cumulative Redeemable Preferred Stock      
Entity Information [Line Items]      
Title of 12(b) Security 7.00% Series D Cumulative Redeemable Preferred Stock, par value $0.001 per share    
Trading Symbol GOODM    
Security Exchange Name NASDAQ    
6.625% Series E Cumulative Redeemable Preferred Stock      
Entity Information [Line Items]      
Title of 12(b) Security 6.625% Series E Cumulative Redeemable Preferred Stock, par value $0.001 per share    
Trading Symbol GOODN    
Security Exchange Name NASDAQ