Estimated reduction in payments under Maritime Security Program due to budget reduction.

No definition available.

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- Definition

Represents number of top executives will vest the grant date.

+ References

No definition available.

+ Details

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(b)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(a)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

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Subsequent Events (Details) (USD $) In Millions, except Share data, unless otherwise specified			0 Months Ended
	Mar. 31, 2013 Restricted Stock Units (RSUs) [Member] Executive	Dec. 31, 2012 Restricted Stock Units (RSUs) [Member]	Apr. 23, 2013 Subsequent Event [Member] Executive	Apr. 23, 2013 Subsequent Event [Member] Performance Shares [Member]	Apr. 23, 2013 Subsequent Event [Member] Performance Shares [Member] Executive Officer [Member]	Apr. 23, 2013 Subsequent Event [Member] Restricted Stock Units (RSUs) [Member]
Subsequent Event [Line Items]
Units granted (in shares)			87,300
Number of units to be vested (in shares)	42,014	65,500		7,050		80,250
Period over which units will be vested				3 years	1 year
Number of top executives	4		4
Estimated impact on Maritime Security Program due to budget reduction			$ 2