REVENUE (Tables)

6 Months Ended

Jun. 30, 2020

REVENUE [Abstract]

Schedule of Disaggregated Revenue

The following table presents the Company’s revenues from leases accounted for under ASC 842 and revenues from services accounted for under ASC 606 for the three and six months ended June 30, 2020 and 2019:

	Crude		Product
(Dollars in thousands)	Tankers		Carriers		Other		Totals
Three months ended June 30, 2020:
Revenues from leases
Pool revenues	$	72,446	$	27,613	$	—	$	100,059
Time and bareboat charter revenues		26,655		—		—		26,655
Voyage charter revenues from non-variable lease payments		2,690		1,705		—		4,395
Voyage charter revenues from variable lease payments		50		—		—		50
Revenues from services
Voyage charter revenues
Lightering services		8,566		—		—		8,566
Total shipping revenues	$	110,407	$	29,318	$	—	$	139,725
Three months ended June 30, 2019:
Revenues from leases
Pool revenues	$	28,247	$	16,466	$	—	$	44,713
Time and bareboat charter revenues		6,451		90		—		6,541
Voyage charter revenues from non-variable lease payments		5,239		324		—		5,563
Voyage charter revenues from variable lease payments		842		—		—		842
Revenues from services
Voyage charter revenues
Lightering services		11,351		—		—		11,351
Total shipping revenues	$	52,130	$	16,880	$	—	$	69,010

	Crude		Product
(Dollars in thousands)	Tankers		Carriers		Other		Totals
Six months ended June 30, 2020:
Revenues from leases
Pool revenues	$	142,696	$	58,572	$	—	$	201,268
Time and bareboat charter revenues		35,259		—		—		35,259
Voyage charter revenues from non-variable lease payments		10,043		2,406		—		12,449
Voyage charter revenues from variable lease payments		1,170		—		—		1,170
Revenues from services
Voyage charter revenues
Lightering services		14,916		—		—		14,916
Total shipping revenues	$	204,084	$	60,978	$	—	$	265,062
Six months ended June 30, 2019:
Revenues from leases
Pool revenues	$	74,419	$	37,931	$	—	$	112,350
Time and bareboat charter revenues		11,971		90		—		12,061
Voyage charter revenues from non-variable lease payments		12,511		348		—		12,859
Voyage charter revenues from variable lease payments		1,190		—		—		1,190
Revenues from services
Voyage charter revenues
Lightering services		32,424		—		—		32,424
Total shipping revenues	$	132,515	$	38,369	$	—	$	170,884

Schedule of Contract Related Receivables, Assets and Liabilities with Customers

The following table provides information about receivables, contract assets and contract liabilities from contracts with customers, and significant changes in contract assets and liabilities balances, associated with revenue from services accounted for under ASC 606. Balances related to revenues from leases accounted for under ASC 842 are excluded from the table below.
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(Dollars in thousands)	Voyage receivables - Billed receivables		Contract assets (Unbilled voyage receivables)		Contract liabilities (Deferred revenues and off hires)
Opening balance as of January 1, 2020	$	2,727	$	—	$	—
Closing balance as of June 30, 2020		2,941		571		—