Debt - (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2018	Dec. 31, 2017	Dec. 31, 2014
Debt Instrument [Line Items]
Principal	$ 55,993	$ 56,160
Unamortized Discount and Debt Issuance Costs	540	530
Debt	$ 55,453	55,630
Debt interest rate			4.80%
Effective interest rate	4.90%
Construction loan \| Refinanced loan in the Pier Park North JV, due November 2025, bearing interest at 4.1%
Debt Instrument [Line Items]
Principal	$ 47,080	47,295
Unamortized Discount and Debt Issuance Costs	495	512
Debt	$ 46,585	$ 46,783
Debt interest rate	4.10%	4.10%
Construction loan \| Pier Park outparcel construction loan, due March 2027, bearing interest at LIBOR plus 1.7% (effective rate of 3.6% at March 31, 2018)
Debt Instrument [Line Items]
Principal	$ 1,624
Unamortized Discount and Debt Issuance Costs	18
Debt	$ 1,606
Basis interest rate	1.70%	1.70%
Effective interest rate	3.60%	3.30%
Construction loan \| WaterColor Crossings construction loan, due February 2029, bearing interest at LIBOR plus 1.7% (effective rate of 3.6% at March 31, 2018)
Debt Instrument [Line Items]
Principal	$ 33
Unamortized Discount and Debt Issuance Costs	27
Debt	$ 6
Basis interest rate	1.70%
Effective interest rate	3.60%
Secured debt \| Community Development District debt, secured by certain real estate or other collateral, due May 2031 - May 2039, bearing interest at 3.6% to 7.0% at March 31, 2018
Debt Instrument [Line Items]
Principal	$ 7,256	$ 7,241
Unamortized Discount and Debt Issuance Costs	0	0
Debt	$ 7,256	7,241
Secured debt \| Pier Park outparcel construction loan, due March 2027, bearing interest at LIBOR plus 1.7% (effective rate of 3.6% at March 31, 2018)
Debt Instrument [Line Items]
Principal		1,624
Unamortized Discount and Debt Issuance Costs		18
Debt		$ 1,606
Minimum \| Construction loan \| Community Development District debt, secured by certain real estate or other collateral, due May 2031 - May 2039, bearing interest at 3.6% to 7.0% at March 31, 2018
Debt Instrument [Line Items]
Debt interest rate	3.60%	3.60%
Maximum \| Construction loan \| Community Development District debt, secured by certain real estate or other collateral, due May 2031 - May 2039, bearing interest at 3.6% to 7.0% at March 31, 2018
Debt Instrument [Line Items]
Debt interest rate	7.00%	7.00%

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

No definition available.

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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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

+ Details

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- Definition

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

+ References

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399

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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/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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