INCOME TAXES (Details) - USD ($) $ in Thousands		3 Months Ended		6 Months Ended
	Jan. 01, 2018	Dec. 31, 2017	Dec. 31, 2016	Jun. 30, 2018	Dec. 31, 2017	Dec. 31, 2016
Income tax expense		$ (48,360)	$ (5,044)		$ (55,904)	$ (12,232)
Effective tax rate (as a percent)		148.50%	15.70%		83.90%	18.50%
Non-cash functional currency election		$ 15,900
Net reduction in income tax expense due to Tax Cuts and Jobs Act		26,400
Mandatory transition tax due to tax legislation		$ 11,500
Mandatory transition tax payment period		8 years
Re-measurement of net deferred tax assets and liabilities due to tax legislation		$ (2,300)
Re-measurement of foreign uncertain tax positions due to tax legislation		$ 17,200
Forecast
Effective tax rate (as a percent)				28.10%
US corporate income tax rate (as a percent)	21.00%