Commitments and Contingencies - Additional Information (Details) ft² in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) ft² Property	Dec. 31, 2016 USD ($) ft² Property	Dec. 31, 2015 USD ($)	Apr. 03, 2017 ft² Property
Other Commitments [Line Items]
Number of industrial properties | Property	488
Outstanding amount of letters of credit and performance bonds in the aggregate | $	$ 20,188
Gross leasable area (GLA) of industrial properties | ft²	60,200
Insurance Deductible | $	$ 25
Operating and ground lease expense | $	$ 1,419	$ 1,380	$ 1,281
Leases with purchase options
Other Commitments [Line Items]
Number of industrial properties | Property	4
Development Activity
Other Commitments [Line Items]
Number of industrial properties | Property	11
Gross leasable area (GLA) of industrial properties | ft²	4,200
Estimated total investment | $	$ 291,000
Estimated total investment remaining to be funded | $	$ 175,800
2016 Fire
Other Commitments [Line Items]
Number of industrial properties | Property		1
Gross leasable area (GLA) of industrial properties | ft²		30
2017 Fire
Other Commitments [Line Items]
Number of industrial properties | Property				1
Gross leasable area (GLA) of industrial properties | ft²				80