Business Combinations (Acquisition Expenses And Related Adjustments By Type) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Transaction closing expenses	$ 16	$ 3	$ 22
Restructuring, severance and relocation	31	6	9
Integration Related Costs	25	22	12
Gain on business combination	(81)	0	0
Total Acquisition and Integration Related Costs	(9)	31	43
Other income: reimbursement of post-acquisition interest expense from former shareholders	0	0	(16)
Interest expense: bridge loan fees	11	0	25
Total Acquisition Expenses and Related Adjustments	$ 2	$ 31	$ 52

Business combination cost reimbursement expense from former shareholders

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- Definition

Restructuring, Serverance and Relocation Costs Related to Acquisitions

+ References

No definition available.

+ Details

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- Definition

Transaction and integration expenses that are directly related to acquisitions by the Company. Examples include transaction closing costs, professional service fees, restructuring or severance charges, retention payments, employee relocation expenses, facility or other exit-related expenses, recoveries of acquisition-related expenses or post-closing expenses, and gains or losses on business combinations, excluding any adjustments to non-operating income and expenses.

+ References

No definition available.

+ Details

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- Definition

Transaction and integration expenses that are directly related to acquisitions by the Company. Examples include transaction closing costs, professional service fees, restructuring or severance charges, retention payments, employee relocation expenses, facility or other exit-related expenses, recoveries of acquisition-related expenses or post-closing expenses, bridge loan fees, and gains or losses on business combinations.

+ References

No definition available.

+ Details

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- Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e1043-128460

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 141R

-Paragraph 59

-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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- Definition

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

+ References

No definition available.

+ Details

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- Definition

In a business combination achieved in stages, this element represents the amount of gain recognized by the entity as a result of remeasuring to fair value the equity interest in the acquiree it held before the business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (g)(2)

-URI http://asc.fasb.org/extlink&oid=7659399&loc=d3e1392-128463

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- Definition

Represents the charge against earnings during the period for commitment fees and debt issuance expenses.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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