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The weighted average exercise price at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Amount of the required periodic payments including both interest and principal payments.

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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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SUBSEQUENT EVENTS (Details) $ / shares in Units, $ in Thousands						3 Months Ended	12 Months Ended
	Mar. 04, 2019 $ / shares shares	Feb. 28, 2019 USD ($) item	Jan. 28, 2019 USD ($)	May 31, 2018 USD ($)	Feb. 27, 2018 shares	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2016 USD ($) shares
Subsequent Events
Gain on sale of vessels							$ 3,513	$ 7,712	$ 3,555
Secured Debt \| $460 Million Credit Facility
Subsequent Events
Maximum borrowing capacity				$ 460,000			$ 460,000
Reference rate				LIBOR
Percentage limit of consolidated net income for which dividends can be paid				50.00%
Collateral vessel replacement period				120 days
Secured Debt \| $460 Million Credit Facility \| Minimum
Subsequent Events
Collateral security maintenance test (as a percent)				135.00%
Secured Debt \| $460 Million Credit Facility \| Maximum
Subsequent Events
Collateral security maintenance test (as a percent)				200.00%
2015 EIP Plan \| Restricted Stock Units
Subsequent Events
Granted (in shares) \| shares					37,346		51,704	317,595	66,666
Vesting period of awards							3 years
2015 EIP Plan \| Stock Options
Subsequent Events
Options to purchase (in shares) \| shares					122,608		122,608	133,000
Vesting percentage of awards					33.33%
Vesting period of awards					3 years
Subsequent Event \| Genco Vigour
Subsequent Events
Sale of assets			$ 6,550
Broker commission (as a percent)			2.00%
Subsequent Event \| Secured Debt \| $460 Million Credit Facility
Subsequent Events
Maximum borrowing capacity		$ 460,000
Subsequent Event \| Secured Debt \| $35,000 Scrubber Tranche
Subsequent Events
Maximum borrowing capacity		$ 35,000
Number of the Capesize vessels to be financed \| item		17
Reference rate		LIBOR
Percentage limit of consolidated net income for which dividends can be paid		50.00%
Collateral vessel replacement period		180 days
Number of collateral dispositions to invoke reinvestment right \| item		16
Subsequent Event \| Secured Debt \| $35,000 Scrubber Tranche \| Maximum
Subsequent Events
Collateral security maintenance test (as a percent)		200.00%
Subsequent Event \| Forecast \| Genco Vigour
Subsequent Events
Gain on sale of vessels						$ 700
Subsequent Event \| Period To March 30, 2020 \| Secured Debt \| $35,000 Scrubber Tranche
Subsequent Events
Minimum amount required per borrowing		$ 5,000
Subsequent Event \| Period To March 30, 2020 \| Secured Debt \| $35,000 Scrubber Tranche \| Maximum
Subsequent Events
Percentage of scrubber costs to be financed		90.00%
Subsequent Event \| Through September 30, 2019 \| Secured Debt \| $35,000 Scrubber Tranche
Subsequent Events
Applicable margin over reference rate for interest payable		2.50%
Subsequent Event \| Period After September 30, 2019 \| Secured Debt \| $35,000 Scrubber Tranche \| Minimum
Subsequent Events
Applicable margin over reference rate for interest payable		2.25%
Subsequent Event \| Period After September 30, 2019 \| Secured Debt \| $35,000 Scrubber Tranche \| Maximum
Subsequent Events
Applicable margin over reference rate for interest payable		2.75%
Subsequent Event \| Period After March 31, 2020 \| Secured Debt \| $35,000 Scrubber Tranche
Subsequent Events
Debt repayment profile		4 years
Quarterly repayment assuming maximum borrowed		$ 2,500
Subsequent Event \| 2015 EIP Plan \| RSUs and Stock Options
Subsequent Events
Vesting percentage of awards	33.00%
Vesting period of awards	3 years
Subsequent Event \| 2015 EIP Plan \| Restricted Stock Units
Subsequent Events
Granted (in shares) \| shares	106,079
Subsequent Event \| 2015 EIP Plan \| Stock Options
Subsequent Events
Options to purchase (in shares) \| shares	240,540
Exercise price (in dollars per share) \| $ / shares	$ 8.39