Quarterly report pursuant to Section 13 or 15(d)

Organization, Basis of Presentation and Significant Accounting Policies (Details)

v2.4.0.6
Organization, Basis of Presentation and Significant Accounting Policies (Details) (USD $)
 3 Months Ended 1 Months Ended 3 Months Ended
Mar. 31, 2013
Subsidiary
Property
Mar. 31, 2012
Dec. 31, 2012
Feb. 29, 2012
Series C Preferred Stock [Member]
Mar. 31, 2012
Series C Preferred Stock [Member]
Mar. 31, 2013
Real Estate [Member]
Mar. 31, 2012
Real Estate [Member]
Mar. 31, 2013
GCLP Business Trust I [Member]
Mar. 31, 2013
GCLP Business Trust II [Member]
Mar. 31, 2013
Gladstone Commercial Advisers, Inc. [Member]
Mar. 31, 2013
Building and building improvements [Member]
Mar. 31, 2013
Maximum [Member]
Mar. 31, 2012
Maximum [Member]
Mar. 31, 2013
Maximum [Member]
Equipment and fixtures [Member]
Mar. 31, 2013
Minimum [Member]
Mar. 31, 2012
Minimum [Member]
Mar. 31, 2013
Minimum [Member]
Equipment and fixtures [Member]
Organization and Significant Accounting Policies (Textual) [Abstract]                                  
Company ownership percentage of voting securities of Commercial Advisers                   100.00%              
Percentage of limited partnership interest transferred to business unit               99.00% 1.00%                
Number of trust shares exchanged for limited partnership interest               100                  
Number of trust shares exchanged for general partnership interest                 100                
Subsidiary and business trust of the Company, formed under the laws of the Commonwealth of Massachusetts, date               Dec. 28, 2005 Dec. 28, 2005                
Estimated useful life                     39 years     7 years     5 years
Expected lease up period for estimating carrying costs                       18 months     9 months    
Real estate depreciation expense           $ 3,400,000 $ 2,800,000                    
Amortization related to above-market lease                       100,000 100,000        
Amortization related to below-market lease                             200,000 300,000  
Remaining term of in-place leases and unamortized lease                       15 years     10 years    
Series C preferred stock       7.125% 7.125%                        
Percentage of discount rate for calculating undiscounted obligation                       7.60%     2.50%    
Organization and Significant Accounting Policies (Additional Textual) [Abstract]                                  
Number of subsidiaries interest owned in general and limited partnership. 2                                
Total amortization expense related to intangible assets 1,500,000 1,100,000                              
Number of properties impaired 0                                
Impairment charges 0                                
Expiration period of property lease 2014-01                                
Payments of deferred financing costs 141,000 2,387,000                              
Total amortization expense related to deferred financing costs is included in interest expense 405,000 320,000                              
Liabilities accrued 0 0                              
Recorded expenses 31,000 40,000                              
Aggregate undiscounted obligation on properties 9,200,000   9,200,000                            
Expected payment to be made in next twelve months 0                                
Expected payment to be made in second year 0                                
Expected payment to be made in third year 0                                
Expected payment to be made in fourth year 0                                
Expected payment to be made in fifth year 0                                
Non-qualifying income related to real estate portfolio 0                                
Reclassification effect on previously reported net income $ 0