SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Impairment (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2020 USD ($) item	Mar. 31, 2019 USD ($)	Feb. 24, 2020 item
Impairment of long-lived assets
Impairment of vessel assets | $	$ 112,814	$ 0
Number impaired vessel assets | item	4
Number of vessels to be disposed | item			10
Genco Picardy, Genco Predator, Genco Provence and Genco Warrior
Impairment of long-lived assets
Impairment of vessel assets | $	$ 27,046
Baltic Hare, Baltic Fox, Baltic Wind, Baltic Cove, Baltic Breeze, Genco Ocean, Genco Bay, Genco Avra, Genco Mare and Genco Spirit
Impairment of long-lived assets
Impairment of vessel assets | $	$ 85,768
Baltic Wind, Baltic Breeze and Genco Bay
Impairment of long-lived assets
Number of vessels to be disposed | item	3