Organization - Narrative (Details)	12 Months Ended
	Dec. 31, 2019 ft² joint_venture property	Dec. 31, 2018 joint_venture property	Dec. 31, 2017 ft² joint_venture property	Dec. 31, 2018 property	Dec. 31, 2018 ft²
Organization [Line Items]
Number of joint ventures | joint_venture	1	2	2
Corporate Joint Venture
Organization [Line Items]
Area of real estate property	2,600,000		3,000,000.0		2,600,000
Number of managed retail properties | property	11	13	15
Retail
Organization [Line Items]
Area of real estate property	8,300,000		12,400,000		9,500,000
Square feet	977,400				470,000
Retail | CARY PARK TOWN CENTER Cary, NC
Organization [Line Items]
Square feet			501,000
Retail
Organization [Line Items]
Number of retail properties	54	1	71	58
Sandy Plains Centre | Retail
Organization [Line Items]
Square feet					125,000