PREMISES AND EQUIPMENT, NET - Summary by Country (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Total	$ 59,980	$ 45,631
United States
Property, Plant and Equipment [Line Items]
Total	27,879	25,693
India
Property, Plant and Equipment [Line Items]
Total	16,269	3,154
Luxembourg
Property, Plant and Equipment [Line Items]
Total	14,503	14,975
Philippines
Property, Plant and Equipment [Line Items]
Total	1,094	1,754
Other
Property, Plant and Equipment [Line Items]
Total	$ 235	$ 55