DEBT - $495 Million Credit Facility (Details) - Secured Debt $ in Thousands										3 Months Ended
	Mar. 12, 2020 USD ($)	Nov. 15, 2019 USD ($)	Nov. 05, 2019 USD ($)	Sep. 23, 2019 USD ($)	Aug. 28, 2019 USD ($)	Apr. 15, 2019 USD ($)	Feb. 28, 2019 USD ($) item	Jun. 05, 2018 USD ($)	May 31, 2018 USD ($) item	Mar. 31, 2020 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2019 USD ($)
$495 Million Credit Facility
Line of Credit Facility
Maximum borrowing capacity							$ 495,000			$ 495,000	$ 495,000	$ 495,000
Debt covenant to pay dividends or repurchase stock - Total cash and cash equivalents to total indebtedness (as a percent)			18.75%
Number of oldest vessels identified for sale for which debt will be paid down | item									7
Remaining borrowing capacity										0
Drawdowns during the period										11,250
Repayment of secured debt										16,660	$ 15,000
Percentage limit of consolidated net income for which dividends can be paid			50.00%
Collateral vessel replacement period			180 days
Key covenant - Unrestricted cash and cash equivalents minimum									$ 30,000
Key covenant – Percentage of unrestricted cash to total indebtedness									7.50%
Minimum restricted cash required									$ 0
Minimum working capital required									$ 0
Maximum total indebtedness to total capitalization (as a ratio)									70
Key covenant – Minimum time charters period									24 months
$495 Million Credit Facility | Genco Champion and Genco Challenger
Line of Credit Facility
Vessel sale proceeds utilized as a loan repayment		$ 6,880
Collateral vessel replacement period		180 days
$495 Million Credit Facility | Genco Cavalier
Line of Credit Facility
Vessel sale proceeds utilized as a loan repayment						$ 4,947
$460 Million Credit Facility
Line of Credit Facility
Term of facilities									5 years
Maximum borrowing capacity									$ 460,000
Number of oldest vessels identified for sale for which debt will be paid down | item									7
Drawdowns during the period								$ 460,000
Repaid value of loan when certain debt terms are met									$ 0
Average age of collateral vessels for repayment of loan									17 years
$460 Million Credit Facility | Period after December 31, 2018
Line of Credit Facility
Amortization payments per quarter									$ 15,000
$460 Million Credit Facility | Period upon final maturity on May 31, 2023
Line of Credit Facility
Final payment amount									$ 190,000
$460 Million Credit Facility | Period After December 30, 2019
Line of Credit Facility
Amount of periodic payment										14,321
Final payment amount												$ 188,049
$460 Million Credit Facility | LIBOR | Through December 31, 2018
Line of Credit Facility
Applicable margin over reference rate (as a percent)									3.25%
$35,000 Scrubber Tranche
Line of Credit Facility
Maximum borrowing capacity			$ 35,000				$ 35,000
Drawdowns during the period	$ 11,250			$ 12,200	$ 9,300					32,750
Number of Capesize vessels for which the scrubber installation will be financed | item							17
$35,000 Scrubber Tranche | Period To March 30, 2020
Line of Credit Facility
Minimum amount required per borrowing							$ 5,000
$35,000 Scrubber Tranche | Period After March 31, 2020
Line of Credit Facility
Term of facilities							4 years
Amount of periodic payment							$ 2,500			$ 2,339
$35,000 Scrubber Tranche | LIBOR | Through September 30, 2019
Line of Credit Facility
Applicable margin over reference rate (as a percent)							2.50%
Minimum | $495 Million Credit Facility
Line of Credit Facility
Debt covenant to pay dividends or repurchase stock - Total cash and cash equivalents			$ 100,000
Collateral security maintenance test (as a percent)									135.00%
Minimum | $460 Million Credit Facility | LIBOR | Period after December 31, 2018
Line of Credit Facility
Applicable margin over reference rate (as a percent)									3.00%
Minimum | $35,000 Scrubber Tranche | LIBOR | Period After September 30, 2019
Line of Credit Facility
Applicable margin over reference rate (as a percent)							2.25%
Maximum | $495 Million Credit Facility
Line of Credit Facility
Collateral security maintenance test (as a percent)			200.00%
Maximum | $460 Million Credit Facility | LIBOR | Period after December 31, 2018
Line of Credit Facility
Applicable margin over reference rate (as a percent)									3.50%
Maximum | $35,000 Scrubber Tranche | Period To March 30, 2020
Line of Credit Facility
Percentage of scrubber costs to be financed							90.00%
Maximum | $35,000 Scrubber Tranche | LIBOR | Period After September 30, 2019
Line of Credit Facility
Applicable margin over reference rate (as a percent)							2.75%