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Related Party Transactions (Details)			1 Months Ended			3 Months Ended	6 Months Ended	12 Months Ended				31 Months Ended
Related Party Transactions (Details)	Jun. 10, 2016 USD ($) townhome Lots	Mar. 01, 2016 USD ($)	Feb. 28, 2017 USD ($)	Jun. 30, 2016 USD ($) Lots	Nov. 30, 2015 USD ($) townhome Lots	Dec. 31, 2017 USD ($) board_seat Lots	Jun. 30, 2017 USD ($) Lots	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($) board_seat Lots	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2018 USD ($)	Mar. 31, 2016	Mar. 30, 2016 townhome Lots	Sep. 30, 2015 townhome Lots
Related Party Transaction [Line Items]
Stockholders' Equity Attributable to Noncontrolling Interest						$ 16,691,000		$ 17,281,000	$ 16,691,000	$ 16,913,000	$ 12,323,000
Centre Living
Related Party Transaction [Line Items]
Noncontrolling Interest, Ownership Percentage by Parent						50.00%			50.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners						50.00%			50.00%
Percentage of Voting Interest						51.00%			51.00%
PercentofCentreLivingOperationsConsolidated									100.00%
Academy Street [Member]
Related Party Transaction [Line Items]
CapitalContributionsMade									$ 500,000	11,200,000
Related Party Transaction, Amounts of Transaction								3,300,000	11,500,000
Proceeds from Distributions Received from Real Estate Partnerships								$ 2,700,000	9,200,000
Selling, General and Administrative Expenses
Related Party Transaction [Line Items]
Rent expense									1,200,000	900,000	700,000
Suwanee Station [Member] \| The Providence Group
Related Party Transaction [Line Items]
Total estimated Capital Contributions						$ 2,500,000			$ 2,500,000
BoardSeatsAvailable \| board_seat						3			3
CapitalContributionsMade									$ 700,000	1,800,000
PaymentsForCapitalContributions									$ 400,000	900,000
BoardSeatsHeld \| board_seat						2			2
Number of lots purchased \| townhome														73
Equity Method Investment, Ownership Percentage														50.00%
EquityMethodInvestment,OwnershipPercentagbyPartner														50.00%
The Parc at Cogburn [Member] \| The Providence Group
Related Party Transaction [Line Items]
Number of townhomes in community \| townhome															19
Number of lots purchased \| Lots							19								11
Payments to acquire residential real estate							$ 1,000,000			300,000	1,800,000
Academy Street [Member]
Related Party Transaction [Line Items]
PaymentsForCapitalContributions									$ 400,000	$ 9,000,000
Academy Street [Member] \| The Providence Group
Related Party Transaction [Line Items]
CapitalContributionsMade												$ 11,700,000
Noncontrolling Interest, Ownership Percentage by Parent													80.00%	80.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners														20.00%
Number of lots purchased \| Lots														83
Glens at Sugarloaf [Member] \| The Providence Group
Related Party Transaction [Line Items]
Number of townhomes in community \| townhome					92									80
Number of lots purchased \| Lots					12
Payments for deposits on real estate acquisitions					$ 0
Payments to acquire residential real estate		$ 4,800,000									$ 1,000,000
Dunwoody Towneship [Member] \| The Providence Group
Related Party Transaction [Line Items]
Number of townhomes in community \| townhome	40
Number of lots purchased \| Lots	14					26			26
Payments to acquire residential real estate	$ 1,800,000								$ 3,300,000
Developed Lots [Member] \| Centre Living
Related Party Transaction [Line Items]
ContractPriceEmployeeDiscountPremium									13.00%
Number of lots purchased \| Lots				1
Proceeds from Sale of Real Estate				$ 400,000
Cost of Land and Lots Sales				$ 300,000
Development in Process						$ 600,000			$ 600,000
townhome [Member] \| Officer [Member]
Related Party Transaction [Line Items]
ContractPriceEmployeeDiscountPremium			13.00%
Richard A. Costello [Member] \| Centre Living
Related Party Transaction [Line Items]
Proceeds from Sale of Real Estate						500,000
Related Party Deposit Liabilities			$ 100,000
Jed Dolson [Member] \| Centre Living
Related Party Transaction [Line Items]
Proceeds from Sale of Real Estate						$ 500,000
Related Party Deposit Liabilities			$ 100,000
GHO Homes [Member] \| Office Space Lease Agreements [Member] \| Affiliated Entity [Member]
Related Party Transaction [Line Items]
Due to Related Parties												$ 0