EQUITY METHOD INVESTMENTS - Summary of Equity Method Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Income from equity method investments	$ 955	$ 0
Total Equity method investments	97,803	0
Manufacturing JV
Schedule of Equity Method Investments [Line Items]
Equity method investment, unerlying equity in net assets	75,434	0
Manufacturing JV Capital Contribution
Schedule of Equity Method Investments [Line Items]
Equity method investment, unerlying equity in net assets	10,714	0
HK JV and China JV
Schedule of Equity Method Investments [Line Items]
Equity method investment, unerlying equity in net assets	$ 10,700	$ 0