Stock Compensation Plans (Details 3) (Unaudited) (Stock Awards Plan, USD $) In Thousands, except Per Share data, unless otherwise specified	9 Months Ended	12 Months Ended
Sep. 30, 2011 Year	Sep. 30, 2010	Dec. 31, 2010 Year
Stock Awards Plan
Stock Award Activity (Table Amounts)
Stock awards - outstanding at January 1	4,300
Stock awards - granted	1,640	2,200
Stock awards - vested	(56)
Stock awards - forfeited	(322)
Stock awards - Shipbuilding Spin-off adjustments	(252)
Stock awards - outstanding at September 30	5,310		4,300
Weighted-average grant date fair value - outstanding at January 1	$ 53
Weighted-average grant date fair value - granted	$ 63	$ 60
Weighted-average grant date fair value - vested	$ 65
Weighted-average grant date fair value - forfeited	$ 50
Weighted-average grant date fair value - Shipbuilding Spin-off adjustments	$ 47
Weighted-average grant date fair value - outstanding at September 30	$ 53		$ 53
Weighted-average remaining contractual term - outstanding at January 1 (years)	1.2		1.5
Weighted-average remaining contractual term - outstanding at September 30 (years)	1.2		1.5

The number of shares under a share-based award plan other than a stock option plan that were settled during the reporting period as a result of the shipbuilding spinoff transaction.

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The weighted average fair value of nonvested awards on share-based plans excluding option plans (for example, phantom stock plan, stock appreciation rights plan, revenue or profit achievement stock award plan) for which the employer was contingently obligated to issue equity instruments relating to the spun-off Shipbuilding Company.

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The weighted average period between the balance-sheet date and vesting of stock awards outstanding under the plan, which may be expressed in a decimal value for number of years.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

The weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect during the reporting period as a result of the occurrence of a terminating event specified in the contractual agreement of the plan.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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

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

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

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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

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-Paragraph A240

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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-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.

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

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-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.

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-Name Accounting Standards Codification

-Topic 718

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-Paragraph 2

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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