Real Estate Investments - Acquisitions (Details) ft² in Millions			3 Months Ended
	Apr. 29, 2016 USD ($) shares	Jan. 14, 2016 USD ($) ft² portfolio	Jun. 30, 2016 USD ($)
Eleven Asset Retail Portfolio
Real Estate Properties
Number of acquired assets in portfolio (portfolio) | portfolio		11
Area of property (in square feet) | ft²		1.1
Acquisition, total consideration		$ 170,500,000
Purchase price adjustment resulted in increase in below-market leases			$ 5,100,000
Purchase price adjustment resulted in decrease in income producing property			$ 5,100,000
Southgate Square
Real Estate Properties
Acquisition, total consideration	$ 39,500,000
Acquisition, common units issued (in shares) | shares	1,575,185
Period for option to buy adjacent land, option one (in years)	2 years
Future payment for option to buy adjacent land, option one	$ 3,000,000.0
Period for option to buy adjacent land, option two (in years)	1 year
Future payment for option to buy adjacent land, option two	$ 1,250,000
Southgate Square | Class A units
Real Estate Properties
Acquisition, assumption of debt	$ 21,100,000