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VESSELS (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2021 USD ($) Vessel	Jul. 28, 2021 Vessel	Dec. 31, 2020 USD ($) Vessel
VESSELS [Abstract]
Number of vessels | Vessel	23		23
Vessels [Abstract]
Impairment loss on vessels	$ 0
Vessels and Drydocking	1,399,754		$ 1,398,690
Less Accumulated Depreciation	(571,791)		(537,348)
Vessels, net	$ 827,963		$ 861,342
Number of vessels in drydock for periodical maintenance | Vessel	1
Number of vessels in drydock for periodical maintenance on later date | Vessel	3
Vessels Built in 2000 and 2002 [Member] | Subsequent Event [Member]
Vessels [Abstract]
Number of vessels to be sold | Vessel		1
Vessels Built in 2000 and 2002 [Member] | Minimum [Member]
Vessels [Abstract]
Vessels, net	$ 14,800
Vessels Built in 2000 and 2002 [Member] | Minimum [Member] | Subsequent Event [Member]
Vessels [Abstract]
Number of vessels intended to be disposed of | Vessel		2
Vessels Built in 2000 and 2002 [Member] | Maximum [Member]
Vessels [Abstract]
Vessels, net	$ 28,700

X

- Definition

The number of vessels in drydock for periodical maintenance survey as of the balance sheet date.

+ References

No definition available.

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- Definition

The number of vessels in drydock for periodical maintenance survey later than the balance sheet date.

+ References

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- Definition

The number of vessels that are intended to be disposed of.

+ References

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- Definition

The number of vessels that are intended to be sold.

+ References

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- Definition

Amount before accumulated depreciation of vessels used in the normal conduct of business and not intended for resale.

+ References

No definition available.

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- Definition

Carrying amount at the balance sheet date of vessels used in the normal conduct of business and not intended for resale, net of accumulated depreciation on vessels.

+ References

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- Definition

The number of vessels under the operational management at of the balance sheet date.

+ References

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- Definition

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

The aggregate amount of write-downs for impairments recognized during the period for long-lived assets held for abandonment, exchange or sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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