Share-based Compensation (Summary of Share Options Outstanding and Exercisable) (Details) (USD $) In Millions, except Share data	6 Months Ended
Jun. 30, 2011	Dec. 31, 2010
Range of Exercise Prices, Minimum	$ 30.06
Range of Exercise Prices, Maximum	$ 48.02
Outstanding Options, Number	1,510,536	1,837,990
Outstanding Option, Weighted Average Price	$ 42.29	$ 42.39
Exercisable Options, Number	1,026,417
Exercisable Options, Weighted Average Price	$ 44.87
Aggregate intrinsic value of outstanding options	$ 32.4
Aggregate Intrinsic Value of Exercisable Options	$ 19.4
Closing Share Price per Share for Calculation of Aggregate Intrinsic Values	$ 63.62
$30.06-$41.91[Member]
Range of Exercise Prices, Minimum	$ 30.06
Range of Exercise Prices, Maximum	$ 41.91
Outstanding Options, Number	550,956
Outstanding Option, Weighted Average Price	$ 33.04
Exercisable Options, Number	257,251
Exercisable Options, Weighted Average Price	$ 36.43
$42.90-$44.00 [Member]
Range of Exercise Prices, Minimum	$ 42.90
Range of Exercise Prices, Maximum	$ 44.00
Outstanding Options, Number	342,063
Outstanding Option, Weighted Average Price	$ 43.53
Exercisable Options, Number	304,800
Exercisable Options, Weighted Average Price	$ 43.48
$45.53-$73.32 [Member]
Range of Exercise Prices, Minimum	$ 45.53
Range of Exercise Prices, Maximum	$ 73.32
Outstanding Options, Number	617,517
Outstanding Option, Weighted Average Price	$ 49.85
Exercisable Options, Number	464,366
Exercisable Options, Weighted Average Price	$ 50.45

Closing share price per share for calculation of aggregate intrinsic values.

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- Definition

Share Based Compensation Shares Authorized Under Stock Options Plans Exercise Price Range Exercisable Options Weighted Average Exercise Price.

+ Details

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- Definition

The weighted average price as of the balance sheet date at which grantees could acquire the underlying shares with respect to all outstanding stock options which are in the customized range of exercise prices.

+ Details

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- Definition

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices of vested portions of options outstanding and currently exercisable under the option plan as of the balance-sheet date.

+ Details

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- Definition

The total dollar difference between fair values of the underlying shares reserved for issuance and exercise prices pertaining to options outstanding under the plan as of the balance-sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph d(1)

+ Details

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- Definition

The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64

+ Details

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- Definition

The number of shares reserved for issuance pertaining to the outstanding exercisable stock options as of the balance-sheet date in the customized range of exercise prices for which the market and performance vesting condition has been satisfied.

+ 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(1)(c)

+ Details

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- Definition

The number of shares reserved for issuance pertaining to the outstanding stock options as of the balance sheet date for all option plans in the customized range of exercise prices.

+ 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(1)(a, b)

+ Details

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- Definition

The ceiling of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 64

+ Details

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