Long-Term Debt (Deferred Financing Costs) (Details) - USD ($) $ in Thousands	Jun. 30, 2015	Dec. 31, 2014
Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Gross carrying amount	$ 3,638	$ 3,638
Accumulated amortization	(1,455)	(1,091)
Net	2,183	2,547
Revolving Credit Facility Maturing June 2018 [Member]
Debt Instrument [Line Items]
Gross carrying amount	14,787	13,275
Accumulated amortization	(5,351)	(3,982)
Net	9,436	9,293
Convertible Senior Notes 2032 [Member]
Debt Instrument [Line Items]
Gross carrying amount	3,759	3,759
Accumulated amortization	(2,070)	(1,763)
Net	1,689	1,996
MARAD Debt [Member]
Debt Instrument [Line Items]
Gross carrying amount	12,200	12,200
Accumulated amortization	(6,467)	(6,223)
Net	5,733	5,977
Nordea Term Loan [Member]
Debt Instrument [Line Items]
Gross carrying amount	3,607	3,586
Accumulated amortization	(120)
Net	3,487	3,586
Debt [Member]
Debt Instrument [Line Items]
Gross carrying amount	37,991	36,458
Accumulated amortization	(15,463)	(13,059)
Net	$ 22,528	$ 23,399