Condensed Consolidated Statements of Cash Flows - USD ($)	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Cash flows from operating activities:
Net (loss)/income	$ (4,562,989)	$ 29,483	$ 2,584,822	$ 52,745	$ (10,525,662)	$ 6,088,334
Adjustments to reconcile net (loss)/income to net cash provided by operating activities:
Depreciation					24,845,206	24,115,813
Amortization of operating lease right-of-use asset					9,480,487	0
Amortization of deferred drydocking costs					4,379,162	3,893,254
Amortization of debt discount and debt issuance costs	1,136,445		463,618		2,265,374	1,433,971
Amortization of fair value below contract value of time charter acquired					0	(511,426)
Loss on debt extinguishment	0		0		2,268,452	0
Gain on sale of vessels	(971,129)		(235,695)		(6,044,479)	(340,768)
Net unrealized loss/(gain) on fair value of derivatives					138,354	(52,506)
Stock-based compensation expense	1,155,223		2,100,056		3,827,902	8,020,566
Drydocking expenditures					(6,062,439)	(6,536,478)
Changes in operating assets and liabilities:
Accounts payable					(1,799,292)	1,438,208
Accounts receivable					1,889,818	1,103,935
Accrued interest					5,927,043	4,161,502
Inventories					1,853,870	836,648
Operating lease liabilities short and long-term					(10,024,158)	0
Other current and non-current assets					(1,010,905)	(553,987)
Other accrued liabilities and other non-current liabilities					144,279	(4,061,872)
Prepaid expenses					1,171,960	742,357
Unearned revenue					(3,770,762)	(1,287,723)
Net cash provided by operating activities					18,954,210	38,489,828
Cash flows from investing activities:
Purchase of vessel and vessel improvements					(81,365,090)	(20,043,324)
Advance paid for purchase of vessels, scrubbers and ballast water systems					(50,537,160)	(8,182,119)
Proceeds from redemption of short-term investment					0	4,500,000
Proceeds from hull and machinery insurance claims					2,112,426	0
Proceeds from sale of vessels					29,626,659	20,545,202
Purchase of other fixed assets					(228,122)	(148,770)
Net cash used in investing activities					(100,391,287)	(3,329,011)
Cash flows from financing activities:
Cash used to settle net share equity awards					(877,697)	(2,018,195)
Cash received from exercise of stock options					0	4,866
Other financing costs					(830,237)	(1,428,792)
Net cash provided by financing activities					104,396,889	157,879
Net increase in cash, cash equivalents and restricted cash					22,959,812	35,318,696
Cash, cash equivalents and restricted cash at beginning of period		$ 78,163,638		$ 56,325,961	78,163,638	56,325,961	$ 56,325,961
Cash, cash equivalents and restricted cash at end of period	$ 101,123,450		$ 91,644,657		101,123,450	91,644,657	$ 78,163,638
SUPPLEMENTAL CASH FLOW INFORMATION
Cash paid during the period for interest					13,106,139	13,627,434
Accruals for scrubbers and ballast water treatment systems included in Accounts payable and Other accrued liabilities					8,867,952	0
Accruals for debt issuance costs included in Other accrued liabilities					418,224	0
Accrual for liability relating to taxes on net share equity awards included in Other accrued liabilities					471,236	0
New First Lien Facility
Cash flows from financing activities:
Repayment of revolver loan under New First Lien Facility					(5,000,000)	(5,000,000)
Proceeds from debt					5,000,000	0
Repayments of long-term debt					(60,000,000)	0
Ultraco Debt Facility
Cash flows from financing activities:
Proceeds from debt					0	8,600,000
Repayments of long-term debt					(82,600,000)	0
Norwegian Bond Debt Facility
Cash flows from financing activities:
Repayments of long-term debt					(4,000,000)	0
New Ultraco Debt Facility
Cash flows from financing activities:
Proceeds from debt					153,440,000	0
Repayments of long-term debt					(10,097,342)	0
Debt issuance costs paid to lenders on New Ultraco Debt Facility					(3,156,250)	0
Convertible Bond Debt
Cash flows from financing activities:
Proceeds from debt					112,482,586	0
Share Lending Agreement
Cash flows from financing activities:
Proceeds from debt					$ 35,829	$ 0