Investment in Real Estate Investment in Real Estate - Summary of Industrial Property Acquisitions (Details) $ in Thousands, ft² in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) ft² Property	Dec. 31, 2018 USD ($) ft² Property	Dec. 31, 2017 USD ($) ft² Property
Real Estate Properties [Line Items]
Number of industrial properties | Property	440
Gross leasable area (GLA) of industrial properties | ft²	61.3
Acquisition Activity
Real Estate Properties [Line Items]
Number of industrial properties | Property	9	10	8
Gross leasable area (GLA) of industrial properties | ft²	0.5	1.0	1.1
Purchase price of industrial properties acquired | $	$ 147,887	$ 167,546	$ 174,209