Real Estate Acquisitions (Details) ft² in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) ft² real_estate_property
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of properties acquired | real_estate_property	10
Area of real estate property (in square feet) | ft²	145
Aggregate purchase price	$ 28,500
Cash consideration	$ 29,311
Percentage of properties that were leased at acquisition	95.20%
Revenue from properties acquired	$ 210
Net income (loss) from properties acquired	83
General and Administrative Expense [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Transaction costs	393
10 Properties Acquired in First Quarter 2017 [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cash consideration	28,400
Property Adjacent To Corporate Property [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cash consideration	$ 900