Area of land sold in the reporting period.

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The amount of expense provided in the period for legal and third party costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings. References

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Amount of cash outflow to settle environmental loss contingencies.

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Area of land held.

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Total anticipated costs associated with remediation, site restoration, postclosure, monitoring commitments, or other exit costs that may occur on the sale, disposal, or abandonment of a particular property resulting from unanticipated contamination of the assets.

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Carrying amount of the liability for remediation of environmental damage pertaining to assets or businesses previously disposed.

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Estimate of reasonably possible loss exposure in excess of amount accrued for remediation, site restoration, postclosure, monitoring commitments, or other exit costs associated with the sale, disposal or abandonment of a particular property resulting from unanticipated contamination of the assets.

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Amount of cash outflow associated with funds that are not available for withdrawal or use (such as funds held in escrow) and are associated with underlying transactions that are classified as investing activities.

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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 loss contingency liability.

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Amount of cash and cash equivalents restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

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COMMITMENTS AND CONTINGENCIES - Other Matters (Details)				3 Months Ended						6 Months Ended		12 Months Ended		21 Months Ended	30 Months Ended
COMMITMENTS AND CONTINGENCIES - Other Matters (Details)	Aug. 01, 2018 a	Jun. 30, 2017 USD ($) a item	Jun. 30, 2016 USD ($)	Jun. 30, 2018 USD ($) a	Mar. 31, 2018 a	Dec. 31, 2017 USD ($)	Jun. 30, 2017 USD ($) a	Mar. 31, 2017 USD ($) a	Jun. 30, 2016 USD ($)	Jun. 30, 2018 USD ($) a	Jun. 30, 2017 USD ($) a	Dec. 31, 2017 USD ($)	Dec. 31, 2015 USD ($) a	Dec. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Feb. 21, 2018 USD ($)
Contingencies
Acres sold \| a	4,286						81.4	1,587.4
Escrow balance		$ 4,727,381		$ 2,419,686		$ 6,508,131	$ 4,727,381			$ 2,419,686	$ 4,727,381	$ 6,508,131		$ 6,508,131	$ 2,419,686	$ 918,000
Unfavorable regulatory action
Contingencies
Accrued loss contingency													$ 187,500
Wintergreen Advisers, LLC maters
Contingencies
Cost incurred												1,600,000		3,000,000
Legal representation and third party costs										$ 944,000		1,200,000
Minto Communities LLC
Contingencies
Acres sold \| a								1,581
Number of mitigation credits required to be utilized \| item		36
Land Sales
Contingencies
Acres sold \| a				32.4	34.9					67.3	1,668.8
Wetlands restoration
Contingencies
Acres \| a													148.4
Estimated cost			$ 2,000,000						$ 2,000,000	$ 2,000,000					2,000,000
Increase in accrual of remediation costs									$ 300,000
Environmental costs funded										1,600,000					1,600,000
Accrued restoration cost				$ 464,000				$ 708,000		$ 464,000			$ 1,700,000		$ 464,000
Wetlands restoration \| Minto Communities LLC
Contingencies
Cash deposited in (refunded from) escrow						189,500	$ 423,000
Escrow balance						$ 234,000						$ 234,000		$ 234,000
Wetlands restoration \| Minimum
Contingencies
Estimated cost													1,700,000
Wetlands restoration \| Maximum
Contingencies
Estimated cost													$ 1,900,000
Mitigation activities
Contingencies
Acres \| a		54.66					54.66				54.66
Mitigation credits transferred							$ 298,000