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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Concentration of Credit Risk (Details) $ in Thousands | 12 Months Ended
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Dec. 31, 2021 USD ($) Charter Customer | Dec. 31, 2020 USD ($) Charter Customer | Dec. 31, 2019 Customer
Concentration of Risk [Abstract] |  |  |
Accounts receivable, net | $ | $ 9,400 | $ 6,300 |
Provision for credit losses | $ | $ 75,000 | $ 25,000 |
Accounts Receivable [Member] | Two Charterers [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Number of charterers accounted for outstanding amount | Charter |  | 2 |
Accounts Receivable [Member] | Three Charterers [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Number of charterers accounted for outstanding amount | Charter | 3 |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Two Charterers [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Concentration of credit risk percentage |  | 39.00% |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Three Charterers [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Concentration of credit risk percentage | 48.00% |  |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Charterer One [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Concentration of credit risk percentage | 22.30% | 22.00% |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Charterer Two [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Concentration of credit risk percentage | 13.30% | 17.00% |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Charterer Three [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Concentration of credit risk percentage | 12.40% |  |
Revenues [Member] | Customer Concentration Risk [Member] | One Customer [Member] |  |  |
Concentration of Risk [Abstract] |  |  |
Number of customers | Customer | 1 | 1 | 1
Concentration of credit risk percentage | 12.50% | 11.40% | 13.70%

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- Definition Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 954 -SubTopic 310 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=123366838&loc=d3e3073-115593 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(5)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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- Definition Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 11B -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-04.11) -URI http://asc.fasb.org/extlink&oid=120399700&loc=SL114874048-224260 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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