FAIR VALUE OF FINANCIAL INSTRUMENTS - NONRECURRING (Details)	3 Months Ended
Sep. 30, 2017 item
Fair Value, Measurements, Nonrecurring \| Genco Surprise
Fair value of financial instruments
Number of vessels written down as part of impairment	5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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