Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
Period Type:	duration

RiverTown Impact Fees (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended								12 Months Ended
RiverTown Impact Fees (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Real estate sale
Revenues		$ 42,660	$ 32,856	$ 35,546	$ 16,023	$ 16,301	$ 23,676	$ 50,434	$ 19,865	$ 127,085	$ 110,276	$ 100,038
Mattamy - RiverTown sale
Real estate sale
Impact fees received	$ 23,100									1,300	23,700	900
Revenues								$ 23,100
Residential real estate \| Operating Segments
Real estate sale
Revenues										$ 41,586	43,266	$ 22,248
Residential real estate \| Operating Segments \| Real estate - Impact fees \| Mattamy - RiverTown sale
Real estate sale
Revenues											$ 23,100