Useful Lives of Property and Equipment Used in Computation of Depreciation (Detail)	12 Months Ended
Dec. 31, 2011 Year
Ships
Property, Plant and Equipment [Line Items]
Property plant equipment, useful life	30
Ship improvements
Property, Plant and Equipment [Line Items]
Property Plant Equipment, useful lives	Shorter of remaining ship life or useful life (3-20)
Property Plant Equipment, useful life minimum	3
Property Plant Equipment, useful life maximum	20
Buildings and improvements
Property, Plant and Equipment [Line Items]
Property Plant Equipment, useful life minimum	10
Property Plant Equipment, useful life maximum	40
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property Plant Equipment, useful life minimum	3
Property Plant Equipment, useful life maximum	5
Transportation equipment and other
Property, Plant and Equipment [Line Items]
Property Plant Equipment, useful life minimum	3
Property Plant Equipment, useful life maximum	30
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property Plant Equipment, useful lives	Shorter of remaining lease term or useful life (3-30)
Property Plant Equipment, useful life minimum	3
Property Plant Equipment, useful life maximum	30

Describes the periods of time over which an entity anticipates to receive utility from its property, plant and equipment (that is, the periods of time over which an entity allocates the initial cost of its property, plant and equipment).

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6367646&loc=d3e18780-107790

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-URI http://asc.fasb.org/subtopic&trid=2155824

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- Definition

The average useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

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- Definition

The maximum useful life of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

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- Definition

The minimum useful life of long lived, physical assets used in the normal conduct of business and not intended for resale. Examples include land, buildings, machinery and equipment, and other types of furniture and equipment including, but not limited to, office equipment, furniture and fixtures, and computer equipment and software.

+ References

No definition available.

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