REVENUE (Schedule of Disaggregated Revenue) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Revenue, non lease	$ 125,337	$ 101,874
Shipping revenues	125,337	101,874
Lightering Services Component [Member]
Revenue, non lease	6,350	21,073
International Crude Tankers Segment [Member]
Revenue, non lease	93,677	80,385
Shipping revenues	93,677	80,385
International Crude Tankers Segment [Member] \| Lightering Services Component [Member]
Revenue, non lease	6,350	21,073
International Product Carriers Segment [Member]
Revenue, non lease	31,660	21,489
Shipping revenues	31,660	21,489
Pool Revenue Leases [Member]
Shipping revenues	101,209	67,637
Pool Revenue Leases [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	101,209	67,637
Pool Revenue Leases [Member] \| International Crude Tankers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	70,250	46,172
Pool Revenue Leases [Member] \| International Product Carriers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	30,959	21,465
Voyage Charter Leases Non Variable Payments [Member] \| Fixed-Price Contract [Member]
Revenue, lease non-variable	8,054	7,296
Voyage Charter Leases Non Variable Payments [Member] \| International Crude Tankers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, lease non-variable	7,353	7,272
Voyage Charter Leases Non Variable Payments [Member] \| International Product Carriers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, lease non-variable	701	24
Voyage Charter Leases Variable Payments [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	1,120	348
Voyage Charter Leases Variable Payments [Member] \| International Crude Tankers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	1,120	348
Time and Bareboat Charter Leases [Member]
Shipping revenues	8,604	5,520
Time and Bareboat Charter Leases [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	8,604	5,520
Time and Bareboat Charter Leases [Member] \| International Crude Tankers Segment [Member] \| Fixed-Price Contract [Member]
Revenue, operating leases	8,604	5,520
Voyage Charter Leases [Member]
Shipping revenues	$ 15,524	$ 28,717

Amount of non-variable lease payments from operating, direct financing, and sales-type leases, excluding amount included in measurement of lease receivable.

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Amount of operating lease income from lease payments and variable lease payments paid and payable to lessor. Includes, but is not limited to, variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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