Employee Stock-Based Compensation (Details Textual) (USD $)	9 Months Ended
Sep. 30, 2011
Stock Options [Member]
Employee Stock-Based Compensation (Textuals)
Stock options granted	694,805
Expiration period of stock options granted from date of grant	10 years
Vesting period of stock options granted	3 years
Weighted average grant date fair value of stock options	$ 15.54
Restricted Stock Units [Member]
Employee Stock-Based Compensation (Textuals)
Units granted	687,422
Vesting period of units granted for employees	3 years
Vesting period of units granted for non-employee directors	1 year
Weighted average grant date fair value	$ 80.17
Performance Units [Member]
Employee Stock-Based Compensation (Textuals)
Units granted	81,765
Vesting period of units granted for employees	3 years
Weighted average grant date fair value	$ 95.50
Maximum payout range	200.00%
Minimum payout range	0.00%

Employee Stock Based Compensation Textuals.

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- Definition

Maximum payout range for performance units based on pre-determined performance goals established by the compensation committee.

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Minimum payout range for performance units based on pre-determined performance goals established by the compensation committee.

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- Definition

Description of the estimated period of time over which a non-employee director is required to wait in exchange for the share-based payment award to vest.

+ Details

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- Definition

Reflects the dating as to when the share-based award expires as specified in the award agreement, which may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

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- Definition

Description of the estimated period of time over which an employee is required to provide service in exchange for the share-based payment award, which often is the vesting period. This period may be explicit or implicit based on the terms of the award, and may be presented in a variety of ways (for example, year, month and year, day, month and year, quarter of a year).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

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- Definition

Description of the period of time over 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, which may be expressed in a variety of ways (for example, in years, month and year).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph a

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- Definition

The number of shares issuable under a share-based award plan pertaining to grants made during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

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- Definition

The weighted average fair value at grant for nonvested share-based awards issued during the period on other than stock option plans (for example, phantom stock plan, stock appreciation rights plan, performance target plan).

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph b(2)(c)

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-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

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- Definition

The difference between the maximum number of shares authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares already issued upon exercise of options or other share-based awards under the plan, and 2) shares reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

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