Quarterly report pursuant to Section 13 or 15(d)

Summary Of Significant Accounting Policies (Narrative) (Details)

v3.21.1
Summary Of Significant Accounting Policies (Narrative) (Details)
 3 Months Ended 12 Months Ended 15 Months Ended
Mar. 31, 2021
USD ($)
segment
property
shares
Mar. 31, 2020
USD ($)
Dec. 31, 2020
USD ($)
Mar. 31, 2021
USD ($)
customer
Summary Of Significant Accounting Policies [Line Items]        
Common units in operating partnership | shares 7,305,355      
Land and building held for development, net $ 42,870,000   $ 40,397,000 $ 42,870,000
Cash and cash equivalents maximum benchmark (in months) 3 months      
Minimum expected future benefit period on expenditures cost to be capitalized and depreciated (in years) 2 years      
Minimum expected future benefit period on transaction cost to be capitalized and depreciated (in years) 1 year      
Length of time criteria for expected sale of assets to be classified as properties held for disposition 12 months      
Below market lease, net $ 2,000,000.0   2,200,000 2,000,000.0
Below market leases, accumulated amortization 12,400,000   12,200,000 12,400,000
Impairment on assets 0 $ 0    
Operating lease, right-of-use asset 1,400,000   1,500,000 1,400,000
Operating lease, liability 1,400,000   1,500,000 1,400,000
Accumulated amortization 200,000   200,000 200,000
Rental income 108,047,000 106,216,000    
Rental income, operating leases 82,100,000 81,600,000    
Rental income, variable lease payments 25,900,000 $ 24,600,000    
Income tax expense 0      
Tax benefit for uncertain tax positions $ 0   0  
Number of operating segments | segment 2      
Number of reportable segments | segment 1      
Gross real estate investment property $ 3,061,862,000   3,050,713,000 3,061,862,000
Land and building held for development 42,870,000   40,397,000 42,870,000
Properties held for sale, net 25,698,000   26,273,000 $ 25,698,000
Reclassification [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Land and building held for development, net     (2,600,000)  
Gross real estate investment property     (23,700,000)  
Land and building held for development     (2,600,000)  
Properties held for sale, net     26,300,000  
COVID-19 [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Deferral agreement, number of customers | customer       398
Deferral agreement, percentage of customers on a percentage of total rental income basis       11.00%
Deferred rent receivable 200,000     $ 5,900,000
Rent receivable abated 100,000     1,400,000
Deferred payments received $ 3,900,000      
Collection rate percentage on deferral repayments 98.50%      
Above Market Leases [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Finite-lived intangible assets, net $ 1,100,000   1,200,000 1,100,000
Finite-lived intangible assets, accumulated amortization (11,200,000)   (11,100,000) (11,200,000)
Acquired In Place Leases [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Finite-lived intangible assets, net 4,600,000   5,300,000 4,600,000
Finite-lived intangible assets, accumulated amortization $ 7,900,000   7,200,000 $ 7,900,000
Minimum [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Estimated useful life (in years) 5 years      
Operating lease, expiration date 2029      
Operating lease, remaining lease term 8 years 6 months      
Maximum [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Estimated useful life (in years) 30 years      
Operating lease, expiration date 2030      
Operating lease, remaining lease term 8 years 9 months 18 days      
Highgate at the Mile [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Number of units to be developed | property 395      
Highgate at the Mile [Member] | JV Partner [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Consolidated entity ownership percentage 5.00%     5.00%
Brentford at The Mile [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Number of units to be developed | property 411      
Gross real estate investment property $ 5,500,000     $ 5,500,000
Brentford at The Mile [Member] | JV Partner [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Consolidated entity ownership percentage 1.80%     1.80%
Investment in Joint Venture [Member] | Highgate at the Mile [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Consolidated entity ownership percentage 95.00%     95.00%
Investment in Joint Venture [Member] | Brentford at The Mile [Member]        
Summary Of Significant Accounting Policies [Line Items]        
Consolidated entity ownership percentage 98.20%     98.20%
Land and building held for development, net $ 25,500,000   15,100,000 $ 25,500,000
Land and building held for development $ 25,500,000   $ 15,100,000 $ 25,500,000