Acquisitions and Dispositions (Summary of Significant Assumptions Utilized in Estimates) (Details)	Mar. 31, 2019 $ / sqft
Industrial [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Net rental rate per square foot	5.90
Industrial [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Net rental rate per square foot	7.08
Measurement Input, Cap Rate [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Fair Value Inputs, Capitalization Rate	4.23%
Measurement Input, Cap Rate [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Fair Value Inputs, Capitalization Rate	4.62%