Annual report pursuant to Section 13 and 15(d)

Recent Transactions (Land Impairments) (Narrative) (Details)

v3.10.0.1
Recent Transactions (Land Impairments) (Narrative) (Details)
$ in Thousands
12 Months Ended
Dec. 31, 2018
USD ($)
property
Property, Plant and Equipment [Line Items]  
Land impairments | $ $ 24,566
Conshohocken And Bala Cynwyd, Pennsylvania [Member] | Land [Member]  
Property, Plant and Equipment [Line Items]  
Number of real estate properties | property 2