Represents the percentage of compensation withheld for purchase of shares of the entity's common stock.

No definition available.

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- Definition

Represents the number of grants approved 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

No definition available.

+ Details

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Period Type:	duration

- Definition

Description of the period of time, from the grant date, after which the equity-based award expires.

+ References

No definition available.

+ Details

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- Definition

Represents the number of share options (or share units) grants approved for issuance during the period.

+ References

No definition available.

+ Details

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- Definition

Represents the performance measurement period used to grant shares under equity-based compensation arrangement.

+ References

No definition available.

+ Details

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- Definition

Represents the performance multiplier used to grant shares under equity-based compensation arrangement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

Represents the maximum number of shares offering in a period under the employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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- Definition

Represents the maximum number of shares offering per plan year under the employee Stock Purchase Plan.

+ References

No definition available.

+ Details

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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 2

-Subparagraph (h)(1)(i)

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

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Staff Accounting Bulletin (SAB)

-Number Topic 14

-Section F

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph 64

-Subparagraph b

-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 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SAB TOPIC 14.F)

-URI http://asc.fasb.org/extlink&oid=6793087&loc=d3e301413-122809

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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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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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Period Type:	duration

- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

+ Details

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

- Definition

Period 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, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units 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

-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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

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

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- 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)

-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 Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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

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Balance Type:	na
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STOCK INCENTIVE PLANS (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended						12 Months Ended	1 Months Ended								1 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013 Restricted stock units	Mar. 31, 2013 Stock options	Mar. 31, 2012 Stock options	Dec. 31, 2010 2010 LTIP	Dec. 31, 2010 2010 LTIP Maximum	Mar. 31, 2013 2013 Awards NQOs	Mar. 31, 2013 2013 Awards Time-based RSU	Mar. 31, 2013 2013 Awards Performance Shares multiplier	Mar. 31, 2012 2012 Awards NQOs	Mar. 31, 2012 2012 Awards Time-based RSU	Mar. 31, 2012 2012 Awards Performance Shares multiplier	Mar. 31, 2013 ESPP	May 31, 2012 ESPP	May 31, 2012 ESPP Maximum
Stock incentive plans
Number of shares available for issuance						11.0								0.9	1.0
Expiration period							10 years
Stock-based compensation expense	$ 5	$ 7
Grants approved (in shares)								0.4			0.8
Performance multiplier										2			2
Performance measurement period										3 years			3 years
Grants approved (in shares)									0.2	0.2		0.6	0.3
Vesting period								3 years	3 years		3 years	3 years
Weighted average fair value of options granted (in dollars per share)				$ 9.92	$ 8.14					$ 27.27			$ 25.38
Unrecognized compensation expense
Remaining unrecognized compensation expense associated with unvested awards				8
Remaining unrecognized compensation expense associated with unvested shares or units			$ 18
Weighted average period for recognition			2 years	2 years
Number of shares offering per period															0.1
Number of shares offering per plan year															0.3
Percentage of compensation withheld for purchase of shares																10.00%