Real Estate Acquisitions, Schedule of Land Acquired (Details) $ in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) site development_site
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | site	2,275
Payments to Acquire Land	$ 14.0
Ocean West [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	26
Payments to Acquire Land	$ 0.2
Water Oak [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	296
Payments to Acquire Land	$ 1.9
Oak Crest [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	220
Payments to Acquire Land	$ 4.2
Pecan Park [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	158
Payments to Acquire Land	$ 1.3
Smith Creek Crossing [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	310
Payments to Acquire Land	$ 0.9
Apple Carr Village [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	121
Payments to Acquire Land	$ 0.2
River Run Ranch [Member]
Business Acquisition [Line Items]
Number of Units in Real Estate Property, Land Development Sites | development_site	1,144
Payments to Acquire Land	$ 5.3