Subsequent Events (Details)			1 Months Ended	9 Months Ended		12 Months Ended
	Oct. 22, 2018 USD ($)	Jun. 28, 2017 USD ($)	Jan. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)	Nov. 06, 2018 scrubber	Oct. 17, 2018 USD ($)	Dec. 29, 2017 USD ($)
Subsequent Event [Line Items]
Payments of financing costs				$ 0	$ 918,000
Subsequent Event
Subsequent Event [Line Items]
Number of scrubbers | scrubber							4
Number of holders of bonds represented							66.67%
Percent support by bondholders							85.36%
Ultraco Debt Facility
Subsequent Event [Line Items]
Proceeds from issuance of long-term debt				8,600,000	$ 61,200,000
Ultraco Debt Facility | Ultraco Lenders
Subsequent Event [Line Items]
Proceeds from issuance of long-term debt			$ 8,600,000	69,800,000
Payments of financing costs			$ 100,000
Deposits on vessel purchases				$ 4,200,000		$ 2,200,000
Ultraco Debt Facility | Ultraco Lenders | Subsequent Event
Subsequent Event [Line Items]
Proceeds from issuance of long-term debt	$ 12,800,000
Payments of financing costs	$ 200,000
Ultraco Debt Facility | Ultraco Lenders | Eagle Bulk Ultraco LLC
Subsequent Event [Line Items]
Increase in commitments									$ 8,600,000
Payments of financing costs		$ 500,000
Ultraco Debt Facility | Ultraco Lenders | Eagle Bulk Ultraco LLC | Subsequent Event
Subsequent Event [Line Items]
Increase in commitments								$ 12,800,000