SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) - USD ($)	Sep. 30, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 907,530,000	$ 85,688,000
Restricted Cash and Cash Equivalents Items [Line Items]
Cash and cash equivalents	907,530,000	85,688,000
Restricted cash and cash equivalents – current	10,952,000	0
Restricted cash and cash equivalents – non-current	4,000,000	4,144,000
Deposits	6,900,000	0
Pinal Land Holdings, LLC
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents – non-current	4,000,000.0	0
Minimum
Restricted Cash and Cash Equivalents Items [Line Items]
Deposits	100
Maximum
Restricted Cash and Cash Equivalents Items [Line Items]
Deposits	5,000
Money Market
Restricted Cash and Cash Equivalents Items [Line Items]
Restricted cash and cash equivalents – current	$ 4,100,000
Restricted cash and cash equivalents – non-current		$ 4,100,000

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes 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. Excludes cash and cash equivalents within disposal group and discontinued operation.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as current. 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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Amount of cash and cash equivalents restricted as to withdrawal or usage, classified as noncurrent. 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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