SEGMENT REPORTING - Revenue and Assets (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Revenue and long lived assets
Revenue	$ 107,701	$ 122,132	$ 123,245	$ 128,115	$ 128,531	$ 138,795	$ 99,991	$ 89,686	$ 481,193	$ 457,003	$ 355,369
Long-Lived Assets	861,484				680,461				861,484	680,461	381,029
U.S
Revenue and long lived assets
Revenue									173,632	198,300	204,024
Long-Lived Assets	358,032				265,528				358,032	265,528	247,169
Guyana
Revenue and long lived assets
Revenue									93,524	91,653	88,894
Long-Lived Assets	129,909				132,609				129,909	132,609	109,829
U.S. Virgin Islands
Revenue and long lived assets
Revenue									83,194	58,431	11,542
Long-Lived Assets	137,018				110,773				137,018	110,773	9,621
Bermuda
Revenue and long lived assets
Revenue									127,244	83,006	45,745
Long-Lived Assets	165,243				94,976				165,243	94,976	13,483
Other Foreign Countries
Revenue and long lived assets
Revenue									3,599	25,613	5,164
Long-Lived Assets	$ 71,282				$ 76,575				$ 71,282	$ 76,575	$ 927