BASIS OF PRESENTATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)			3 Months Ended		6 Months Ended
	Jan. 01, 2015 $ / item	Dec. 31, 2014 USD ($) $ / item	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($) segment item	Jun. 30, 2014 USD ($)
NATURE OF BUSINESS
Number of vessels | item					25
Number of operating segments | segment					1
SPOT MARKET VOYAGE CHARTERS
Reserve against due from charterers		$ 2,100,000	$ 3,718,000		$ 3,718,000
TIME CHARTERS
Accrual for unasserted claims relating to time charters		$ 1,455,000	380,000		$ 380,000
VESSELS, NET
Estimated useful life of vessels					25 years
Depreciation expense			9,755,000	$ 10,673,000	$ 19,390,000	$ 21,240,000
Estimated useful life of vessel leasehold improvements					10 years
Estimated scrap value (in dollars per lightweight ton) | $ / item	325	265
Average period of scrap value of steel					15 years
Decrease in depreciation expense			700,000		$ 1,401,000
Increase to net income per basic and diluted common share as a result of decrease in depreciation			0.01		0.03
VESSELS UNDER CONSTRUCTION
Capitalized interest costs			4,074,000	$ 2,392,000	11,472,000
Capitalized interest paid					7,056,000	2,104,000
Accrued capitalized interest					4,416,000
GOODWILL
Goodwill		$ 27,131,000	$ 27,131,000		$ 27,131,000
IMPAIRMENT OF LONG-LIVED ASSETS
Industry average trailing period considered for forecasting future charter rates and vessel operating costs					10 years
Minimum
NATURE OF BUSINESS
Period of time for which vessels are placed under time charter basis					1 year
Maximum
NATURE OF BUSINESS
Period of time for which vessels are placed under time charter basis					3 years
VESSELS, NET
Estimated useful life of vessels					5 years
VLCCs
NATURE OF BUSINESS
Number of vessels | item					7
New building construction | item					21
Suezmax
NATURE OF BUSINESS
Number of vessels | item					11
Aframax
NATURE OF BUSINESS
Number of vessels | item					4
Panamax
NATURE OF BUSINESS
Number of vessels | item					2
Handymax
NATURE OF BUSINESS
Number of vessels | item					1
Vessels under construction.
VESSELS UNDER CONSTRUCTION
Capitalized interest costs					$ 11,472,000	$ 2,392,000
Capitalized interest paid					7,056,000
Accrued capitalized interest					$ 4,416,000