DEBT (Summary of Interest Expense and Other Costs (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Mar. 29, 2010
Interest and debt expense	$ 35,978	$ 42,781	$ 70,335
Debt instrument, interest rate, stated percentage				8.125%
8.125% Notes due 2018
Interest and debt expense	$ 5,568	$ 10,200	22,779
Debt instrument, interest rate, stated percentage	8.125%	8.125%		8.125%
OBS Facilities [Member]
Interest and debt expense	$ 30,308	$ 32,460	37,666
7.50% Election 1 Notes Due 2021 - 2024 [Member]
Interest and debt expense	$ 102	$ 121	$ 9,890