Investment in Unconsolidated Joint Ventures - Carolina Square Holdings LP (Details) ft² in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($) ft² apartment_unit	Jan. 31, 2021 USD ($)
Schedule of Equity Method Investments [Line Items]
Aggregate outstanding indebtedness	$ 230.3
Carolina Square Holdings LP
Schedule of Equity Method Investments [Line Items]
Ownership percentage of partner in joint venture	50.00%
Number of apartment units | apartment_unit	246
Maximum percentage guaranteed under construction loan	12.50%
Cash balance of joint venture	$ 4.8
Carolina Square Holdings LP | Subsequent Event
Schedule of Equity Method Investments [Line Items]
Aggregate outstanding indebtedness		$ 77.0
Carolina Square Holdings LP | LIBOR
Schedule of Equity Method Investments [Line Items]
Basis spread on variable rate (percent)	1.25%
Carolina Square Holdings LP | Office Space
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (square feet) | ft²	158
Carolina Square Holdings LP | Retail Space
Schedule of Equity Method Investments [Line Items]
Square footage of real estate property (square feet) | ft²	44
Carolina Square Holdings LP | Northwood Ravin
Schedule of Equity Method Investments [Line Items]
Ownership percentage of partner in joint venture	50.00%