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GENERAL INFORMATION (Details 1) (USD $)	0 Months Ended
GENERAL INFORMATION (Details 1) (USD $)	Jul. 09, 2014	Dec. 31, 2014	Dec. 31, 2013	Apr. 21, 2014	Dec. 31, 2012	Aug. 20, 2010	Aug. 12, 2010	Jul. 27, 2010
Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Reorganization Value	1,230,000,000
Projected amount of debt to be on balance sheet of the Debtors	250,000,000
2007 Credit Facility \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Bankruptcy claims settled by conversion into shares of entity (as a percent)	100.00%
$253 Million Term Loan Facility
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt		165,568,000
Maximum borrowing capacity		253,000,000
$253 Million Term Loan Facility \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Maximum borrowing capacity		253,000,000
$100 Million Term Loan Facility
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt		67,792,000
Maximum borrowing capacity		100,000,000
$100 Million Term Loan Facility \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Maximum borrowing capacity		100,000,000
Common Stock \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Number of shares expected to be issued under reorganization	61,700,000
Reorganization value of stock (in dollars per share)	20.00
New Genco MIP Primary Equity shares distribution as percentage of new stock	1.80%
Minimum percentage of new stock providing demand and piggyback registration rights under the registration rights agreement	10.00%
Common Stock \| 2007 Credit Facility \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
New stock issued for bankruptcy claims settlement (as a percent)	81.10%
2010 Notes \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Bankruptcy claims settled by conversion into shares of entity (as a percent)	100.00%
2010 Notes \| Common Stock \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
New stock issued for bankruptcy claims settlement (as a percent)	8.40%
Backstopped rights offering \| Common Stock \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Percentage of new stock offered under offering	8.70%
Aggregate subscription price	100,000,000
Backstopped rights offering \| Common Stock \| 2007 Credit Facility \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Maximum percentage of subscription of new stock under offering	80.00%
Backstopped rights offering \| 2010 Notes \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Maximum percentage of subscription of new stock under offering	20.00%
New Genco Equity Warrants \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Subscription price (in dollars per share)	20.99
Number of warrants issued for old common stock of Genco	3,938,298
Class of Warrant or Right Term	7 years
New Genco Equity Warrants \| Common Stock \| Chapter 11
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Number of shares of new stock in which each warrant or right can be converted	1
Warrants exercisable as percentage of new stock	6.00%
Predecessor
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Outstanding amount of derivatives			6,975,000
Predecessor \| 2007 Credit Facility
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt			1,055,912,000
Predecessor \| 2007 Credit Facility \| Chapter 11 \| GS&T and wholly-owned subsidiaries excluding Baltic Trading Limited
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt				1,055,912,000
Predecessor \| $253 Million Term Loan Facility
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt			180,793,000
Maximum borrowing capacity			253,000,000		253,000,000	253,000,000
Predecessor \| $253 Million Term Loan Facility \| Chapter 11 \| GS&T and wholly-owned subsidiaries excluding Baltic Trading Limited
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt				175,718,000
Predecessor \| $100 Million Term Loan Facility
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt			75,484,000
Maximum borrowing capacity			100,000,000		100,000,000		100,000,000
Predecessor \| Interest rate swap \| Chapter 11 \| GS&T and wholly-owned subsidiaries excluding Baltic Trading Limited
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Outstanding amount of derivatives				5,622,000
Predecessor \| 2010 Notes
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Principal amount of the 2010 Notes			125,000,000
Interest rate on convertible notes (as a percent)								5.00%
Predecessor \| 2010 Notes \| Chapter 11 \| GS&T and wholly-owned subsidiaries excluding Baltic Trading Limited
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Principal amount of the 2010 Notes				125,000,000
Interest rate on convertible notes (as a percent)				5.00%
Predecessor \| $100 Million Term Loan Facility \| Chapter 11 \| GS&T and wholly-owned subsidiaries excluding Baltic Trading Limited
Reorganization under Chapter 11 of US Bankruptcy Code Disclosure [Line Items]
Floating rate debt				$ 73,561,000