CONSOLIDATED STATEMENTS OF INCOME (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
CONSOLIDATED STATEMENTS OF INCOME [Abstract]
Revenues	$ 243,496,000	$ 263,196,000	$ 290,049,000
Operating Expenses:
Voyage Expenses	188,508,000	192,082,000	209,347,000
Vessel Depreciation	24,366,000	25,388,000	17,929,000
Impairment Loss	0	0	25,430,000
Other Depreciation	32,000	0	0
Administrative and General Expenses	23,244,000	20,961,000	21,202,000
Gain on Dry Bulk Transaction	0	(18,844,000)	0
Gain on Sale/Purchase of Other Assets	(16,625,000)	0	(42,000)
Total Operating Expenses	219,525,000	219,587,000	273,866,000
Operating Income	23,971,000	43,609,000	16,183,000
Interest and Other:
Interest Expense	10,409,000	10,361,000	7,157,000
Derivative Loss	485,000	101,000	426,000
(Gain) Loss on Sale of Investments	(580,000)	747,000	(213,000)
Other Income from Vessel Financing	(2,387,000)	(2,653,000)	(2,335,000)
Investment Income	(470,000)	(637,000)	(1,778,000)
Foreign Exchange (Gain) Loss	(5,506,000)	3,051,000	8,196,000
Total Interest and Other Income	1,951,000	10,970,000	11,453,000
Income Before Provision for Income Taxes and Equity in Net Income of Unconsolidated Entities	22,020,000	32,639,000	4,730,000
(Benefit) Provision for Income Taxes:
Current	296,000	680,000	692,000
Deferred	(453,000)	0	(1,982,000)
Income Tax Expense (Benefit)	(157,000)	680,000	(1,290,000)
Equity in Net (Loss) Income of Unconsolidated Entities (Net of Applicable Taxes)	(215,000)	(410,000)	9,282,000
Net Income	$ 21,962,000	$ 31,549,000	$ 15,302,000
Basic and Diluted Earnings per Common Share:
Basic Earnings Per Common Share: (in dollars per share)	$ 3.05	$ 4.42	$ 2.14
Diluted Earnings Per Common Share: (in dollars per share)	$ 3.04	$ 4.40	$ 2.12
Weighted Average Shares of Common Stock Outstanding:
Basic (in shares)	7,195,606	7,131,820	7,158,439
Diluted (in shares)	7,213,288	7,176,647	7,231,178
Dividends Per Share (in dollars per share)	$ 1.000	$ 1.500	$ 1.625