Long-Term Debt (Schedule of Deferred Financing Costs) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Helix Term Loan [Member]
Debt Instrument [Line Items]
Gross Carrying Amount			$ 15,318	[1]
Accumulated Amortization			(11,595)	[1]
Net			3,723	[1]
Helix Revolving Loans [Member]
Debt Instrument [Line Items]
Gross Carrying Amount			20,021	[1]
Accumulated Amortization			(12,466)	[1]
Net			7,555	[1]
Term Loan Maturing June 2018 [Member]
Debt Instrument [Line Items]
Gross Carrying Amount	3,635	[2]
Accumulated Amortization	(182)	[2]
Net	3,453	[2]
Revolving Credit Facility Maturing June 2018 [Member]
Debt Instrument [Line Items]
Gross Carrying Amount	13,272	[2]
Accumulated Amortization	(663)	[2]
Net	12,609	[2]
2025 Notes [Member]
Debt Instrument [Line Items]
Gross Carrying Amount			8,189
Accumulated Amortization			(8,189)
2032 Notes [Member]
Debt Instrument [Line Items]
Gross Carrying Amount	3,759		4,251
Accumulated Amortization	(995)		(534)
Net	2,764		3,717
Senior Unsecured Notes [Member]
Debt Instrument [Line Items]
Gross Carrying Amount			10,643	[3]
Accumulated Amortization			(8,252)	[3]
Net			2,391	[3]
MARAD Debt [Member]
Debt Instrument [Line Items]
Gross Carrying Amount	12,200		12,200
Accumulated Amortization	(5,614)		(5,248)
Net	6,586		6,952
Debt [Member]
Debt Instrument [Line Items]
Gross Carrying Amount	32,866		70,622
Accumulated Amortization	(7,454)		(46,284)
Net	$ 25,412		$ 24,338

[1] Relates to the term loans and revolving credit facility under our former credit agreement, which was terminated in June 2013.

[2] Relates to amounts allocated to the existing Term Loan and Revolving Credit Facility, which became effective in June 2013.

[3] In July 2013, we redeemed our remaining Senior Unsecured Notes. In connection with this redemption, we recorded a charge of $2.1 million to accelerate the remaining deferred financing costs associated with the original issuance of this debt.