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Revenue Recognition (Details) - USD ($)	3 Months Ended								8 Months Ended	12 Months Ended
Revenue Recognition (Details) - USD ($)	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, 2018	Dec. 31, 2017	Dec. 31, 2016	Apr. 26, 2018
Disaggregation of Revenue [Line Items]
Contract with Customer, Performance Obligation Satisfied in Previous Period										$ 0
Revenue, Remaining Performance Obligation, Amount	$ 84,100,000								$ 84,100,000	84,100,000
Revenues	185,120,000	$ 152,052,000	$ 157,312,000	$ 129,163,000	$ 137,424,000	$ 114,342,000	$ 105,750,000	$ 100,734,000		623,647,000	$ 458,250,000	$ 390,985,000
Revenue, Performance Obligation [Abstract]
Revenue, Remaining Performance Obligation, Amount	$ 84,100,000								84,100,000	$ 84,100,000
Revenue, Practical Expedient [Abstract]
Revenue, Practical Expedient, Remaining Performance Obligation, Description										<div style="font-family:Times New Roman;font-size:10pt;"><div style="line-height:120%;text-align:left;text-indent:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our contracts with homebuyers have a duration of less than one year. As such, the Company uses the practical expedient as allowed under ASC 606 and has not disclosed the transaction price allocated to remaining performance obligations as of the end of the reporting period.</font></div></div>
Residential Real Estate [Member]
Disaggregation of Revenue [Line Items]
Revenues										$ 578,893,000	439,520,000	375,821,000
Residential Real Estate [Member] \| Individual Counterparty [Member]
Disaggregation of Revenue [Line Items]
Revenues										578,893,000	439,520,000	375,821,000
Residential Real Estate [Member] \| 1531 Operative Builders [Member]
Disaggregation of Revenue [Line Items]
Revenues										0	0	0
Residential Real Estate [Member] \| Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenues										571,177,000	435,644,000	365,164,000
Residential Real Estate [Member] \| Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues										7,716,000	3,876,000	10,657,000
Residential Real Estate [Member] \| Central [Domain]
Disaggregation of Revenue [Line Items]
Revenues										281,868,000	224,670,000	206,831,000
Residential Real Estate [Member] \| Southeast [Domain]
Disaggregation of Revenue [Line Items]
Revenues										297,025,000	214,850,000	168,990,000
Real Estate, Other [Member]
Disaggregation of Revenue [Line Items]
Revenues										44,754,000	18,730,000	15,164,000
Real Estate, Other [Member] \| Individual Counterparty [Member]
Disaggregation of Revenue [Line Items]
Revenues										0	0	0
Real Estate, Other [Member] \| 1531 Operative Builders [Member]
Disaggregation of Revenue [Line Items]
Revenues										44,754,000	18,730,000	15,164,000
Real Estate, Other [Member] \| Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Revenues										44,754,000	18,730,000	15,164,000
Real Estate, Other [Member] \| Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Revenues										0	0	0
Real Estate, Other [Member] \| Central [Domain]
Disaggregation of Revenue [Line Items]
Revenues										40,184,000	17,928,000	14,201,000
Real Estate, Other [Member] \| Southeast [Domain]
Disaggregation of Revenue [Line Items]
Revenues										4,570,000	802,000	963,000
6552 Land Subdividers and Developers (No Cemeteries) [Member]
Disaggregation of Revenue [Line Items]
Revenues										39,834,000	18,730,000	14,913,000
6552 Land Subdividers and Developers (No Cemeteries) [Member] \| Residential Real Estate [Member]
Disaggregation of Revenue [Line Items]
Revenues										0	0	0
Home Building [Member] \| Central [Domain]
Disaggregation of Revenue [Line Items]
Revenues										282,218,000	224,670,000	206,831,000
Home Building [Member] \| Southeast [Domain]
Disaggregation of Revenue [Line Items]
Revenues										301,595,000	214,850,000	169,241,000
Home Building [Member] \| Real Estate, Other [Member]
Disaggregation of Revenue [Line Items]
Revenues										$ 0	$ 0	$ 0
GHO Homes [Member]
Disaggregation of Revenue [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Contract With Customer, Refund Liability													$ 9,100,000
GHO Homes [Member] \| Residential Real Estate [Member] \| Individual Counterparty [Member]
Disaggregation of Revenue [Line Items]
Contract with Customer, Liability, Revenue Recognized									$ 8,200,000