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Area of land held.

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Amount of environmental remediation costs capitalized. These expenditures may relate to long-lived improvements in operating facilities.

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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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COMMITMENTS AND CONTINGENCIES - Other Matters (Details)					3 Months Ended					12 Months Ended
COMMITMENTS AND CONTINGENCIES - Other Matters (Details)	Apr. 30, 2019 a	Sep. 30, 2017 USD ($) a item	Mar. 31, 2017 USD ($)	Sep. 30, 2016 USD ($)	Mar. 31, 2019 USD ($) a	Mar. 31, 2018 USD ($) a	Dec. 31, 2017 USD ($)	Mar. 31, 2017 a	Jun. 30, 2016 USD ($)	Dec. 31, 2015 USD ($) a	Dec. 31, 2018 USD ($)
Contingencies
Acres sold \| a	3,200
Escrow balance					$ 1,336,361	$ 3,148,997					$ 19,721,475
Potential future costs accrued					$ 0
Unfavorable regulatory action
Contingencies
Accrued loss contingency										$ 187,500
Minto Communities LLC
Contingencies
Acres sold \| a								1,581
Land Sales
Contingencies
Acres sold \| a					9.9	34.9
Wetlands restoration
Contingencies
Acres \| a										148.4
Estimated cost				$ 2,000,000	$ 2,400,000				$ 2,000,000
Increase in accrual of remediation costs					361,000				$ 300,000
Environmental costs funded					1,700,000
Accrued restoration cost					713,000					$ 1,700,000
Wetlands restoration \| Minto Communities LLC
Contingencies
Cash deposited in (refunded from) escrow			$ 423,000		77,833		$ 189,500
Escrow balance					$ 156,000
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
Number of mitigation credits required to be utilized \| item		36
Mitigation credits transferred		$ 298,000