BUSINESS AND SEGMENT REPORTING (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Shipping revenues	$ 1,137,134	$ 1,049,531	$ 1,045,610
Total vessels, deferred drydock and other property at December 31	2,911,706	3,292,946
Us Flag [Member]
Shipping revenues	451,803	377,787	288,249
Total vessels, deferred drydock and other property at December 31	1,008,978	999,935	999,082
International Flag [Member]
Shipping revenues	685,331	671,744	757,361
Total vessels, deferred drydock and other property at December 31	1,902,728	2,293,011	2,246,433
Consolidated [Member]
Shipping revenues	1,137,134	1,049,531	1,045,610
Total vessels, deferred drydock and other property at December 31	$ 2,911,706	$ 3,292,946	$ 3,245,515