ACCUMULATED OTHER COMPREHENSIVE LOSS - Summary (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	$ 3,571,336,000	$ 3,082,391,000	$ 3,551,801,000	$ 2,946,823,000
Total other comprehensive income (loss), net of income taxes	1,091,000	(46,563,000)	2,401,000	(11,170,000)
Balance at end of period	3,843,597,000	3,236,948,000	3,843,597,000	3,236,948,000
Tax provision (benefit) on accumulated other comprehensive loss	0	0	0	0
Foreign Currency Translation Adjustment attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(126,725,000)	(74,950,000)	(128,726,000)	(103,568,000)
Balance at end of period	(125,705,000)	(112,730,000)	(125,705,000)	(112,730,000)
Foreign Currency Translation Adjustment including portion attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss)	1,097,000	(37,266,000)	2,090,000	(9,048,000)
Amounts reclassified to earnings		(191,000)		(52,000)
Total other comprehensive income (loss), net of income taxes	1,097,000	(37,457,000)	2,090,000	(9,100,000)
Foreign Currency Translation Adjustment attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Total other comprehensive income (loss), net of income taxes	(77,000)	(323,000)	931,000	(62,000)
Unrealized Gains on Available-for-Sale Debt Securities attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	6,000	0	4,000	0
Balance at end of period	0	13,000	0	13,000
Unrealized Gains on Available-for-Sale Debt Securities including Portion Attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss)	(6,000)	13,000	(4,000)	13,000
Amounts reclassified to earnings		0		0
Total other comprehensive income (loss), net of income taxes	(6,000)	13,000	(4,000)	13,000
Unrealized Gains on Available-for-Sale Debt Securities attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Total other comprehensive income (loss), net of income taxes	0	0	0	0
Accumulated Other Comprehensive (Loss) Income attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Balance at beginning of period	(126,719,000)	(74,950,000)	(128,722,000)	(103,568,000)
Balance at end of period	(125,705,000)	(112,717,000)	(125,705,000)	(112,717,000)
Accumulated Other Comprehensive (Loss) Income including portion attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive income (loss)	1,091,000	(37,253,000)	2,086,000	(9,035,000)
Amounts reclassified to earnings		(191,000)		(52,000)
Total other comprehensive income (loss), net of income taxes	1,091,000	(37,444,000)	2,086,000	(9,087,000)
Accumulated Other Comprehensive (Loss) Income attributable to Noncontrolling Interest
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Total other comprehensive income (loss), net of income taxes	$ (77,000)	$ (323,000)	$ 931,000	$ (62,000)