Annual report pursuant to Section 13 and 15(d)

Real Estate Joint Ventures (Details)

v3.10.0.1
Real Estate Joint Ventures (Details)
$ in Thousands
1 Months Ended 12 Months Ended
Jul. 21, 2016
USD ($)
Property
Jan. 31, 2016
USD ($)
Dec. 31, 2018
USD ($)
ft²
Dec. 31, 2017
USD ($)
Dec. 31, 2016
USD ($)
Investments in consolidated real estate joint ventures          
Increase in property and redeemable noncontrolling interests in connection with property contributed into a joint venture     $ 0 $ 0 $ 22,600
Distributions paid to redeemable noncontrolling interests     1,382 8,215 15,206
Consolidated real estate joint ventures [Member]          
Investments in consolidated real estate joint ventures          
Total Assets     327,990    
Encumbered Assets     199,049    
Total Liabilities     $ 110,416    
Single-tenant data centers [Member]          
Investments in consolidated real estate joint ventures          
Increase in property and redeemable noncontrolling interests in connection with property contributed into a joint venture $ 147,600        
Ownership percentage sold (percent) 50.00%        
Ownership percentage 50.00%        
Data Center Shells [Member] | Operating properties, net [Member] | Single-tenant data centers [Member]          
Investments in consolidated real estate joint ventures          
Number of properties contributed | Property 6        
Stevens Investors, LLC [Member] | Minimum [Member]          
Investments in consolidated real estate joint ventures          
Percentage of residual distributable cash flows in excess of unpaid cumulative preferred returns and return of invested capital entitled to the company     60.00%    
LW Redstone Company, LLC [Member]          
Investments in consolidated real estate joint ventures          
Partner's capital account upon formation     $ 9,000    
Percentage of residual distributable cash flows in excess of unpaid cumulative preferred returns and return of invested capital entitled to the company     85.00%    
Percentage of residual distributable cash flows in excess of unpaid cumulative preferred returns and return of invested capital entitled to the entity's partners     15.00%    
Number of years following construction commencement threshold achievement before partner's interest can be purchased at fair value     5 years    
Construction commencement threshold (in square feet) | ft²     4,400,000.0    
Construction commencement completed (in sqft) | ft²     751,000    
LW Redstone Company, LLC [Member] | Maximum [Member]          
Investments in consolidated real estate joint ventures          
Infrastructure costs anticipated to be funded by entity for reimbursement by the City of Huntsville (in dollars)     $ 76,000    
Percentage of residual distributable cash flows in excess of unpaid cumulative preferred returns and return of invested capital entitled to the company     85.00%    
LW Redstone Company, LLC [Member] | Notes receivable from City of Huntsville [Member]          
Investments in consolidated real estate joint ventures          
Infrastructure costs funded to date for reimbursement by the City of Huntsville     $ 40,000    
M Square Associates, LLC [Member]          
Investments in consolidated real estate joint ventures          
Percentage of residual amounts distributed to each member     50.00%    
GI-COPT [Member]          
Investments in consolidated real estate joint ventures          
Real estate equity method investments     $ 39,800 41,800  
LW Redstone Company, LLC [Member] | Primary Beneficiary [Member]          
Investments in consolidated real estate joint ventures          
Ownership (as a percent)     85.00%    
Total Assets     $ 169,533    
Encumbered Assets     72,800    
Total Liabilities     $ 50,530    
M Square Associates, LLC [Member] | Primary Beneficiary [Member]          
Investments in consolidated real estate joint ventures          
Ownership (as a percent)     50.00%    
Total Assets     $ 75,339    
Encumbered Assets     43,631    
Total Liabilities     $ 43,869    
Stevens Investors, LLC [Member] | Primary Beneficiary [Member]          
Investments in consolidated real estate joint ventures          
Ownership (as a percent)     95.00%    
Total Assets     $ 83,118    
Encumbered Assets     82,618    
Total Liabilities     $ 16,017    
Increase in property and redeemable noncontrolling interests in connection with property contributed into a joint venture   $ 22,600      
Distributions paid to redeemable noncontrolling interests       $ 6,700 $ 13,400