Share-Based Compensation (Narrative) (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended
Nov. 30, 2011 years	Nov. 30, 2010
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Conversion ratio, number of final trading days in vesting period	40
Capitalized share based compensation	$ 0	$ 0
Purchase of granted nonqualified options	1,933,690	1,879,111
Cash received as a result of stock option exercises	14.7	39.1
Total intrinsic value of options exercised	13.9	34.7
Related tax benefits	5.5	14.0
Weighted average fair values of grant for options per share	$ 13.84	$ 10.80
Unrecognized compensation costs related to nonvested options/MSUs	27.3
Weighted average period, years	2.1
Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, minimum	three
Vesting period, maximum	four
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, minimum	three
Related tax benefits	10.9	7.7
Stock-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, minimum	three
Unrecognized compensation costs related to nonvested options/MSUs	$ 14.4
Weighted average period, years	1.2
Stock units granted, number of units	292,946	277,066
Restricted stock granted, weighted average grant date fair value	$ 45.58	$ 36.24
Cash-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period, minimum	three
Stock units granted, number of units	575,380	688,880
Restricted stock granted, weighted average grant date fair value	$ 32.69	$ 25.39
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash payment per cash settled restricted stock unit	200.00%
Maximum [Member] \| Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options expiration period, term	10
Maximum [Member] \| Stock-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
MSUs converted to common stock	2
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash payment per cash settled restricted stock unit	75.00%
Minimum [Member] \| Stock-Settled Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
MSUs converted to common stock	0

Cash payment per cash settled restricted stock unit

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- Definition

Market Stock Units Converted To Common Stock Conversion Ratio Number Of Final Trading Days In Vesting Period

+ References

No definition available.

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- Definition

Market stock units converted to common stock for each unit granted

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, using a decimal to express in number of years.

+ References

+ Details

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Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

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Balance Type:	credit
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- Definition

The date when the equity-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

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- Definition

The maximum vesting term 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.

+ References

No definition available.

+ Details

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- Definition

The minimum vesting term 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.

+ References

No definition available.

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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)

-Number 123R

-Paragraph A240

-Subparagraph b(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 Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph c(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.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(2)(iii)(1)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

+ 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

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