Debt, Net - Schedule of Debt (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Debt instruments
Debt, Principal	$ 63,953	$ 56,160
Unamortized Discount and Debt Issuance Costs	1,627	530
Debt, Net	62,326	55,630
PPN JV Loan, due November 2025, bearing interest at 4.1%
Debt instruments
Debt, Principal	46,644	47,295
Unamortized Discount and Debt Issuance Costs	462	512
Debt, Net	$ 46,182	$ 46,783
Debt interest rate (as a percent)	4.10%	4.10%
Community Development District debt
Debt instruments
Debt, Principal	$ 6,407	$ 7,241
Debt, Net	$ 6,407	$ 7,241
Community Development District debt \| Minimum
Debt instruments
Debt interest rate (as a percent)	3.60%	3.60%
Community Development District debt \| Maximum
Debt instruments
Debt interest rate (as a percent)	6.00%	7.00%
Pier Park Outparcel Construction Loan, due March 2027, bearing interest at LIBOR plus 1.7%
Debt instruments
Debt, Principal	$ 1,598	$ 1,624
Unamortized Discount and Debt Issuance Costs	17	18
Debt, Net	$ 1,581	$ 1,606
Basis spread on variable rate	1.70%	1.70%
Effective interest rate (as a percent)	4.00%	3.30%
Loan in Pier Park Crossings JV, due June 2060, bearing interest at 4.0%
Debt instruments
Debt, Principal	$ 8,311
Unamortized Discount and Debt Issuance Costs	1,121
Debt, Net	$ 7,190
Debt interest rate (as a percent)	4.00%
WaterColor Crossings Construction Loan, due February 2029, bearing interest at LIBOR plus 1.7%
Debt instruments
Debt, Principal	$ 993
Unamortized Discount and Debt Issuance Costs	27
Debt, Net	$ 966
Basis spread on variable rate	1.70%
Effective interest rate (as a percent)	4.00%

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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