BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - DEFERRED COSTS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
DEFERRED DRYDOCK COSTS, NET
Deferred drydock, amortization	$ 5,700	$ 7,200	$ 5,100
Deferred drydock, accumulated amortization	5,100	13,900
DEFERRED FINANCING COSTS, NET
Deferred financing costs, amortization	15,311	11,792	3,294
Deferred financing costs, amortization	14,900	11,300	$ 3,300
Gener8 Ulysses
DEFERRED DRYDOCK COSTS, NET
Write-off of assets held for sale	$ 1,000	$ 1,000
Minimum
DEFERRED DRYDOCK COSTS, NET
Dry-docking period	30 months
Maximum
DEFERRED DRYDOCK COSTS, NET
Dry-docking period	60 months