Carrying Values of Major Classes of Assets and Liabilities to Charter Fleet Business that are Included in Consolidated Balance Sheet (Detail) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Discontinued Operations And Disposal Groups [Abstract]
Other current assets			$ 3,197
Property, plant and equipment-net			45,892
Other long-term assets			9,679
Total long-term assets held for sale	$ 12,243	$ 26,758	$ 55,571

Long-lived assets that are held for sale apart from normal operations and anticipated to be sold in less than one year.

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- Definition

Other assets that are held for sale apart from normal operations, not otherwise included elsewhere in the taxonomy and which are anticipated to be sold in less than one year, but by their nature which are not considered current (originally classified based on not being realized or converted to working capital within one year of the date of the statement of financial position or operating cycle, if longer).

+ References

+ Details

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- Definition

Property, plant and equipment that is held for sale apart from normal operations and anticipated to be sold in less than one year.

+ References

+ Details

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- Definition

The lower of the carrying value or fair value less cost to sell of current assets held for sale that are not elsewhere specified in the taxonomy. The carrying value of major classes of assets and liabilities of the disposal group are separately disclosed in the balance sheet in the specific concepts provided.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 35

-Paragraph 43

-URI http://asc.fasb.org/extlink&oid=29634951&loc=d3e1739-110224

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