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
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-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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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-Subparagraph (a)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
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, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Real estate sale
Revenues		$ 16,301	$ 23,676	$ 50,434	$ 19,865	$ 21,891	$ 33,988	$ 30,647	$ 13,512	$ 110,276	$ 100,038	$ 96,862
Mattamy - RiverTown sale
Real estate sale
Impact fees received	$ 23,100									23,700	900	400
Residential real estate \| Operating Segments
Real estate sale
Revenues										42,869	$ 21,747	$ 19,483
Residential real estate \| Operating Segments \| Real estate - Impact fees \| Mattamy - RiverTown sale
Real estate sale
Revenues										$ 23,100