SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Other Income, Net Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Other Income, Net [Line Items]
Other Income, Net	$ 33,789	$ 21,619
Total Other Income, Net
Other Income, Net [Line Items]
Other Income, Net	$ 33,800	$ 21,600