Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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FAIR VALUE MEASUREMENTS - Carrying Value and Fair Value of Debt (Details) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Fair Value And Carrying Value By Balance Sheet Grouping
Impairments of equity investments	$ 300,300,000	$ 0	$ 0
Goodwill impairment	536,964,000	0	$ 0
Carrying Amount \| Level 2
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	4,714,442,000	4,910,525,000
Carrying Amount \| Level 2 \| Fixed-rate debt
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	3,546,396,000	4,241,963,000
Carrying Amount \| Level 2 \| Variable-rate debt
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	1,168,046,000	668,562,000
Fair Value \| Level 2
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	4,536,877,000	5,053,240,000
Fair Value \| Level 2 \| Fixed-rate debt
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	3,364,549,000	4,384,336,000
Fair Value \| Level 2 \| Variable-rate debt
Fair Value And Carrying Value By Balance Sheet Grouping
Total debt	1,172,328,000	$ 668,904,000
GMT Caribbean and NYH
Fair Value And Carrying Value By Balance Sheet Grouping
Goodwill impairment	$ 536,964,000