Share-Based Compensation (Narrative) (Details)	6 Months Ended
Jun. 30, 2011
Percentage of stock options vested and exercisable upon change of control	100.00%
Minimum vesting period to consider stock options as one award, in years	1
Dividend yield assumption	0.00%
Target percentage of initial grant	50.00%
Period for measuring performance criteria	three
Percentage of performance based restricted stock awards vested upon change of control units	100.00%
Maximum [Member] \| Restricted Stock Performance-Based Awards [Member]
Performance-based restricted stock award period	100.00%
Minimum [Member] \| Restricted Stock Performance-Based Awards [Member]
Performance-based restricted stock award period	0.00%
Restricted Stock Units Performance-Based Awards [Member]
Percentage of performance based restricted stock awards vested upon change of control units	100.00%
Restricted Stock Units Time-Based Awards [Member]
Percentage of time based restricted stock units vested upon change of control units	100.00%
Restricted Stock Time-Based Awards [Member]
Percentage of shares vested at target level	100.00%

Minimum Vesting Period To Consider Stock Options As One Award.

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- Definition

Percentage of performance based restricted stock awards vested upon change of control units.

+ Details

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- Definition

Percentage of shares vested at target level.

+ Details

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- Definition

Percentage of stock options vested and exercisable upon change of control.

+ Details

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- Definition

Percentage of time based restricted stock units vested upon change of control units.

+ Details

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- Definition

Performance-based restricted stock award period.

+ Details

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- Definition

Share-based compensation target percentage of initial grant.

+ Details

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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 equity-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
-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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph e(2)(c)
-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 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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