ACCUMULATED OTHER COMPREHENSIVE INCOME (Schedule of Components) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			$ 1,593,023
Other comprehensive (loss)/income before reclassifications			(299)		$ 14,064
Amounts reclassified from accumulated other comprehensive income			(770)		(1,503)
Net other comprehensive (loss)/income			(1,069)		12,561
Ending balance	$ 1,600,300		1,600,300		1,593,023
Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			13,417	$ 856	856
Ending balance	12,348		12,348		13,417
Foreign currency translation gains
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			15,975	8,559	8,559
Other comprehensive (loss)/income before reclassifications			(22,997)		7,416
Amounts reclassified from accumulated other comprehensive income			0		0
Net other comprehensive (loss)/income			(22,997)		7,416
Ending balance	(7,022)		(7,022)		15,975
Net investment hedges of New Zealand JV
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			1,665	1,665	1,665
Other comprehensive (loss)/income before reclassifications			(344)		0
Amounts reclassified from accumulated other comprehensive income			0		0
Net other comprehensive (loss)/income			(344)		0
Ending balance	1,321		1,321		1,665
Cash flow hedges
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			16,184	10,831	10,831
Other comprehensive (loss)/income before reclassifications			23,042		7,321
Amounts reclassified from accumulated other comprehensive income			(566)		(1,968)
Net other comprehensive (loss)/income			22,476		5,353
Ending balance	38,660		38,660		16,184
Cash flow hedges | Interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Other comprehensive (loss)/income before reclassifications			26,400
Employee benefit plans
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance			(20,407)	(20,199)	(20,199)
Other comprehensive (loss)/income before reclassifications			0		(673)
Amounts reclassified from accumulated other comprehensive income			(204)		465
Net other comprehensive (loss)/income			(204)		(208)
Ending balance	(20,611)		(20,611)		(20,407)
Pension
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Amortization of losses	168	$ 116	505	$ 349
Accounting Standards Update 2018-02
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative-effect adjustment due to adoption of ASU					0
Accounting Standards Update 2018-02 | Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative-effect adjustment due to adoption of ASU	$ 700		$ 700		(711)
Accounting Standards Update 2018-02 | Retained Earnings
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Cumulative-effect adjustment due to adoption of ASU					$ 711