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LONG-TERM DEBT AND CURRENT PORTION OF LONG TERM DEBT (Details)				2 Months Ended	3 Months Ended	6 Months Ended	12 Months Ended
		Feb. 12, 2019 USD ($)	Dec. 01, 2017 USD ($) Vessel	Sep. 10, 2021 Building	Sep. 28, 2021 USD ($)	Jun. 30, 2021 USD ($) Lender Building Vessel	Dec. 31, 2018 Vessel	Sep. 29, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 16, 2020 USD ($)	Oct. 16, 2020 USD ($)
Line of Credit Facility [Abstract]
Number of lenders | Lender						2
Current portion of long-term debt						$ 22,274,000			$ 22,094,000
Number of new buildings | Building						2
At-the-market Offering of Common Stock						$ 60,000,000
Contractual Obligation [Abstract]
2021	[1]					12,461,000
2022						25,132,000
2023						25,516,000
2024						212,624,000
2025						9,534,000
Thereafter						68,567,000
Total						$ 353,834,000
Subsequent Event [Member]
Line of Credit Facility [Abstract]
Number of new buildings | Building				2
At-the-market Offering of Common Stock								$ 60,000,000
Maximum [Member]
Line of Credit Facility [Abstract]
At-the-market Offering of Common Stock											$ 60,000,000
Maximum [Member] | Subsequent Event [Member]
Line of Credit Facility [Abstract]
At-the-market Offering of Common Stock								$ 60,000,000
2019 Senior Secured Credit Facility [Member]
Line of Credit Facility [Abstract]
Number of vessels used as collateral | Vessel						20
Debt instrument term						5 years
Maximum borrowing capacity		$ 306,100,000
Loan amortizing, maturity period						20 years
Maturity date						Feb. 28, 2024
Discretionary excess cash mechanism for the lender that equals to net earnings from collateral vessels		50.00%
Deferred financing costs		$ 13,000,000.0				$ 2,400,000			2,400,000
Deferred finance costs, non-cash portion		6,100,000
Debt covenants, minimum liquidity		$ 30,000,000.0
Debt covenants percentage in loan-to-vessel ratio		70.00%
Drawn amount						245,500,000			253,900,000
Current portion of long-term debt						14,400,000			14,400,000
Repayment of debt						8,400,000
Contractual Obligation [Abstract]
2021	[1]					8,403,000
2022						16,805,000
2023						16,805,000
2024						203,486,000
2025						0
Thereafter						0
Total						$ 245,499,000
2019 Senior Secured Credit Facility [Member] | Subsequent Event [Member]
Line of Credit Facility [Abstract]
Drawn amount					$ 241,300,000
Repayment of debt					$ 4,200,000
$30 Million Accordion Loan [Member]
Line of Credit Facility [Abstract]
Maximum borrowing capacity										$ 30,000,000.0
Maturity date						Feb. 28, 2024
Financing of 2018-built Vessels [Member]
Line of Credit Facility [Abstract]
Number of vessels delivered | Vessel			3				3
Deferred financing costs			$ 2,300,000
Drawn amount						$ 108,300,000			112,200,000
Percentage of purchase price expected to pay by lending provider			77.50%
Term of bareboat charter agreement						10 years
Obligation to purchase the vessels			$ 13,600,000
First flexibility period to purchase the vessels						60 months
Second flexibility period to purchase the vessels						84 months
Minimum value adjusted equity			$ 175,000,000.0
Minimum value adjusted equity ratio			25.00%
Minimum liquidity value			$ 20,000,000.0
Long term debt current						$ 7,900,000			$ 7,700,000
Number of new buildings | Building						2
Maximum percentage of financing secured						80.00%
Debt						$ 0
Contractual Obligation [Abstract]
2021	[1]					4,058,000
2022						8,327,000
2023						8,711,000
2024						9,138,000
2025						9,534,000
Thereafter						68,567,000
Total						$ 108,335,000
Financing of 2018-built Vessels [Member] | Minimum [Member]
Line of Credit Facility [Abstract]
Interest rate			4.86%
Financing of 2018-built Vessels [Member] | Maximum [Member]
Line of Credit Facility [Abstract]
Interest rate			5.06%
[1] Q3 and Q4 2021 repayments

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The Company has launched an At-the-Market Offering of our common stock and believes that the current cash and cash equivalents and cash expected to be generated from operations are sufficient to meet the working capital needs and other liquidity requirements for the next 12 months.

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