Income Taxes (Narrative) (Details) (USD $)	3 Months Ended		12 Months Ended
	Dec. 31, 2014	Mar. 31, 2013	Dec. 31, 2014 T	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Deferred tax assets, valuation allowance	$ 13,936,000		$ 13,936,000	$ 869,000
Daily notional shipping income per 100 tons of the net tonnage of the vessel in excess of 25000 net tons			0.40
Daily notional shipping income per 100 tons of the net tonnage of the vessel up to 25000 net tons			0.20
Base quantity for calculation of daily notional shipping income			100
Net quantity range considered for calculation of daily notional shipping income			25,000
Foreign income taxes			0	(4,000)	205,000
Income tax current recognition of earnings of foreign subsidiaries			2,500,000	0	2,000,000
Impairment charge	6,600,000
Tonnage tax included in income tax provision (benefit)			52,000	56,000	64,000
Foreign earnings indefinitely reinvested	2,500,000		2,500,000	2,800,000	4,400,000
Increase (decrease) to net operating loss		2,000,000			(2,000,000)
Corporate tax rate			35.00%	35.00%	35.00%
Federal [Member]
Income Taxes [Line Items]
Minimum tax credit carryforwards	5,200,000		5,200,000
Net operating loss carryforwards	47,100,000		47,100,000	41,800,000
Operating Loss Carryforwards Generated During Period			5,300,000
State [Member]
Income Taxes [Line Items]
Net operating loss carryforwards	24,300,000		24,300,000	23,100,000
Operating Loss Carryforwards Generated During Period			1,200,000
Foreign [Member]
Income Taxes [Line Items]
Tax credits that are expected to be utilized on federal return			0
Net operating loss carryforwards	$ 6,400,000		$ 6,400,000
Minimum [Member] | Federal [Member]
Income Taxes [Line Items]
Expiration period			2025
Minimum [Member] | State [Member]
Income Taxes [Line Items]
Expiration period			2025
Maximum [Member] | Federal [Member]
Income Taxes [Line Items]
Expiration period			2034
Maximum [Member] | State [Member]
Income Taxes [Line Items]
Expiration period			2034