Expense related to recognition and retention plans

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- Definition

Number of common stock that had not been awarded.

+ Details

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- Definition

Number of common stock that had not been awarded maximum.

+ Details

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- Definition

Number of common stock that had not been awarded minimum.

+ Details

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Balance Type:	na
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- Definition

Option grant vesting period.

+ Details

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Period Type:	duration

- Definition

Performance options to vest during period.

+ Details

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- Definition

Retention options during period.

+ Details

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- Details

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- Definition

Share based compensation arrangement by share based payment award options grants in period grant date fair value.

+ Details

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- Definition

Stock Based Compensation.

+ Details

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- Definition

Value of cash awards.

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Vesting period to recognize expense.

+ 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

+ Details

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- Definition

Share-based compensation cost during the period with respect to the award, which will be recognized in income (as well as the total recognized tax benefit) or capitalized as part of the cost of an asset.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph g(1)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64, 65

+ Details

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- Definition

The maximum number of shares originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the share-based compensation plan. As stock options and equity instruments other than options are awarded to participants, the shares remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ 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

+ Details

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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.

+ Details

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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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(1)

+ Details

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Stock-Based Compensation (Details Textual) (USD $)	3 Months Ended		9 Months Ended
Stock-Based Compensation (Details Textual) (USD $)	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Stock-Based Compensation (Textual) [Abstract]
Compensation expense related to outstanding stock options	$ 1,900,000	$ 3,000,000	$ 6,400,000	$ 8,200,000
2009 Stock Awards [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	847,750		847,750
Stock Awards Vesting Period			3 years
2009 Stock Awards [Member] \| 2011 SIP [Member]
Stock-Based Compensation (Textual) [Abstract]
Fair Value of the shares on the grant date			$ 12.03
2010 stock awards [Member] \| 2011 SIP [Member]
Stock-Based Compensation (Textual) [Abstract]
Vesting period to recognize expense			3 years
Fair value of the shares on the grant date			$ 13.12
2010 stock awards pursuant to the SIP Plan	18,000		18,000
Stock Option Class One [Member] \| Stock Incentive Plan 2006 [Member]
Stock-Based Compensation (Textual) [Abstract]
Options granted Vesting Period, Maximum			5 years
Options granted Vesting Period, Minimum			1 year
Stock Option Class Two [Member] \| Stock Incentive Plan 2006 [Member]
Stock-Based Compensation (Textual) [Abstract]
Options granted Vesting Period, Maximum			3 years
Options granted Vesting Period, Minimum			2 years
Stock Incentive Plan 2006 [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	30,000,000		30,000,000
Shares remaining under the 2006 SIP Plan	2,070,000		2,070,000
Grants made in prior years pursuant to the SIP plan			23,120,000
Stock Incentive Plan 2011 [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	28,750,000		28,750,000
Options granted Expiration Period			ten years
2011 stock unit awards [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	1,004,230		1,004,230
Total value of stock unit awards	9,700,000		9,700,000
One to Five Years [Member]
Stock-Based Compensation (Textual) [Abstract]
Grants made in prior years pursuant to the SIP plan			6,067,500
Options granted Expiration Period			ten years
Two to Three Years [Member]
Stock-Based Compensation (Textual) [Abstract]
Grants made in prior years pursuant to the SIP plan			17,052,500
Stock Awards [Member]
Stock-Based Compensation (Textual) [Abstract]
Stock Awards Vesting Period			3 years
Total compensation expense for stock awards	870,000	890,000	2,600,000	3,000,000
Stock Unit Awards [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	20,661		20,661
Total value of stock unit awards	250,000		250,000
Total compensation expense for stock awards	$ 872,000	$ 20,833	$ 1,800,000	$ 20,833
2011 SIP [Member]
Stock-Based Compensation (Textual) [Abstract]
Purchase of Common stock, Authorized	1,618,932		1,618,932
Performance options to vest between April 2014 and July 2014	1,308,513		1,308,513
Retention Options to vest in April 2012			310,419