Share-Based Compensation (Details Textuals) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended
Jun. 30, 2011
Additional Share-Based Compensation (Textuals) [Abstract]
Nonvested stock units granted	1.4
Share-Based Compensation (Textuals) [Abstract]
Total unrecognized compensation costs related to share-based awards	$ 244.6
Weighted-average period (in years) to recognize total unrecognized compensation costs as expense	2
Non vested stock units at a weighted average grant price to executive officers and non-executive employees	$ 53.64
Time-based Nonvested Stock Units [Member]
Additional Share-Based Compensation (Textuals) [Abstract]
Period over which nonvested stock units vest	3 years
Market-based Nonvested Stock Units [Member]
Additional Share-Based Compensation (Textuals) [Abstract]
Period over which nonvested stock units vest	50% increments over two- and three-year periods or in annual increments over three years upon achievement of certain targets related to our stock price
Stock Options [Member]
Additional Share-Based Compensation (Textuals) [Abstract]
Issuance of shares related to exercises of stock options and vesting of stock units	0.9
Stock Compensation Plan [Member]
Additional Share-Based Compensation (Textuals) [Abstract]
Issuance of shares related to exercises of stock options and vesting of stock units	1.2

Additional Share-Based Compensation (Textuals) [Abstract].

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- Definition

Share-Based Compensation.

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- Definition

As of the latest balance-sheet date presented, the total compensation cost related to outstanding, nonvested share-based compensation awards not yet recognized (will be charged against earnings as services are performed or other vesting criteria are met).

+ References

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

+ Details

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- Definition

The weighted average period over which unrecognized share-based compensation costs are expected to be reported.

+ References

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

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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)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph A240
-Subparagraph c(1)

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- Definition

The number of shares newly issued during the reporting period under the plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 123R
-Paragraph 65

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-Name Statement of Financial Accounting Standard (FAS)
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