Maximum multiplier used to calculate value of performance shares.

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- Definition

Performance shares granted to certain officers exceeding certain performance measures.

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- Definition

Maximum contractual term of stock options and SSRs, restricted stock and performance shares, year.

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- Definition

Stock-based compensation plans.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

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-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

-Subparagraph g(1)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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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-Publisher FASB

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-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

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-Name Statement of Financial Accounting Standard (FAS)

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- Definition

As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest.

+ References

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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

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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 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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Paragraph A240

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-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

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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.

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-Publisher FASB

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-Subparagraph b(2)(a)

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

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

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

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-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

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- Definition

Net number of share options (or share units) granted during the period.

+ References

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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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Stock-based compensation plans (Details Textuals) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2011 Multiplier	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010
Stock-based compensation plans (Textuals) [Abstract]
Maximum contractual term of stock options and SSRs, restricted stock and performance shares, year			10 years
Weighted average fair value of options granted during the year			$ 17.71
Weighted average fair market value of restricted stock units and performance shares			$ 56.53
Maximum multiplier used to calculate value of performance shares	2.5
Additional performance shares granted			215,000
Total number of non-vested restricted stock and performance share awards	773,000		773,000		950,000
Recognized stock-based compensation expense	$ 10.9	$ 13.1	$ 36.2	$ 37.2
Stock options granted			2,323,000
Restricted stock units and performance shares granted			259,000
Restricted Stock and Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation expense	18.0		18.0
Vesting period of stock option plan			3 years
SSRs and Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unearned compensation expense	$ 32.9		$ 32.9
Vesting period of stock option plan			3 years
2011 LTIP [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum number of shares available for awards under 2011 LTIP	30,000,000		30,000,000