Annual report pursuant to Section 13 and 15(d)

Leasing Activity (Narrative) (Details)

v3.20.4
Leasing Activity (Narrative) (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Operating Leased Assets [Line Items]      
Rental income, variable lease payments $ 96.4 $ 96.5 $ 91.2
Percentage of leased asset subjected to termination options 2.90%    
Percentage of leased asset exercisable in period 1.80%    
Termination option, exercisable through date Dec. 31, 2021    
Minimum [Member]      
Operating Leased Assets [Line Items]      
Non-cancelable lease term 1 year    
Maximum [Member]      
Operating Leased Assets [Line Items]      
Non-cancelable lease term 10 years