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, 2018 pipeline	Dec. 31, 2017 USD ($)	Jan. 01, 2018 USD ($)
Subsidiary or Equity Method Investee [Line Items]
Special cash dividends declared (in dollars per share) | $ / shares	$ 5.00
Special dividend paid	$ 115,900		$ 115,860
Number of water pipelines | pipeline		2
Decrease in deferred tax assets and liabilities, gross			$ 35,600
Cumulative effect adjustment				$ 16
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
Retained Earnings
Subsidiary or Equity Method Investee [Line Items]
Cumulative effect adjustment				560
Accounting Standards Update 2016-01 | Retained Earnings
Subsidiary or Equity Method Investee [Line Items]
Cumulative effect adjustment				$ 560