NATURE OF OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Oct. 31, 2017 USD ($) $ / shares	Dec. 31, 2017 USD ($) pipeline $ / shares shares	Aug. 04, 2017 stock_right	May 31, 2017 $ / shares shares	Dec. 31, 2016 $ / shares shares
Subsidiary or Equity Method Investee [Line Items]
Shares of preferred stock authorized | shares		10,000,000		10,000,000	10,000,000
Par value of preferred stock (in dollars per share)		$ 0.001		$ 0.001	$ 0.001
Special cash dividends declared (in dollars per share)	$ 5.00
Special dividend paid | $	$ 115,900	$ 115,860
Tax benefit preservation plan, beneficial ownership threshold before dilution			4.99%
Number of water pipelines | pipeline		2
Minimum voting interest held in order to be accounted for under the equity method of accounting		20.00%
Maximum voting interest held in order to be accounted for under the equity method of accounting		50.00%
Land Improvements | Minimum
Subsidiary or Equity Method Investee [Line Items]
Estimated useful life		5 years
Buildings and Leasehold Improvements | Minimum
Subsidiary or Equity Method Investee [Line Items]
Estimated useful life		15 years
Buildings and Leasehold Improvements | Maximum
Subsidiary or Equity Method Investee [Line Items]
Estimated useful life		30 years
Furniture and Fixtures
Subsidiary or Equity Method Investee [Line Items]
Estimated useful life		7 years
Computer Equipment
Subsidiary or Equity Method Investee [Line Items]
Estimated useful life		3 years
Tax Preservation Plan
Subsidiary or Equity Method Investee [Line Items]
Ratio of market price to exercise price, causing dilution			2
Number of stock rights issued per common share | stock_right			1