Business and Segment Reporting (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
Total income from vessel operations of all segments	$ 83,386	$ 64,455
General and administrative expenses	(19,282)us-gaap_GeneralAndAdministrativeExpense	(24,425)us-gaap_GeneralAndAdministrativeExpense
Technical management transition costs	(40)	(194)
Severance and relocation costs	(5)us-gaap_SeveranceCosts1	(6,683)us-gaap_SeveranceCosts1	(17,020)us-gaap_SeveranceCosts1
Gain on disposal of vessels	1,073	1,477
Consolidated income from vessel operations	65,132us-gaap_OperatingIncomeLoss	34,630us-gaap_OperatingIncomeLoss
Equity in income of affiliated companies	12,412	8,494
Other income	73us-gaap_NonoperatingIncomeExpense	134us-gaap_NonoperatingIncomeExpense
Interest expense	(28,569)us-gaap_InterestExpense	(123)us-gaap_InterestExpense
Loss before reorganization items and income taxes	$ 49,048	$ 43,135

Amout of Income (Loss) before reorganization items and income taxes during the period.

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This excludes items that are not allocated to a specific segment for segment reporting purposes, such as general and administrative overhead expense.

+ References

No definition available.

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The amount of transition costs related to outsourcing of technical management.

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No definition available.

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- Definition

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

+ References

No definition available.

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The aggregate total of expenses of managing and administering the affairs of an entity, including affiliates of the reporting entity, which are not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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The net result for the period of deducting operating expenses from operating revenues.

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No definition available.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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