SHAREHOLDERS' DEFICIT - Dividends (Details) - USD ($) $ / shares in Units, $ in Thousands						3 Months Ended								12 Months Ended
	Jul. 24, 2015	Apr. 24, 2015	Feb. 20, 2015	Oct. 16, 2014	Jul. 25, 2014	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
SHAREHOLDERS' DEFICIT
Cash dividends declared per common share (in dollars per share)	$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 0.25	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ 0.25	$ 0.25	$ 0.25	$ 0.00	$ 0.75	$ 0.50
Dividends paid														$ 960	$ 87,331	$ 56,988