Income Taxes (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Jun. 30, 2012	Jun. 30, 2011
Income Taxes (Additional Textual) [Abstract]
Income tax expense	$ 130	$ 105
Timing of resolution of income tax examinations	12 months
Significant change in existing unrecognized tax benefits within the next 12 months	$ 200
Period of unrecognized tax benefit	12 months
Effective Income Tax Rate Excluding Discrete Items	32.40%	32.30%
Minimum [Member]
Income Taxes (Textual) [Abstract]
Expected fiscal year 2013 effective tax rate	30.00%
Maximum [Member]
Income Taxes (Textual) [Abstract]
Expected fiscal year 2013 effective tax rate	31.00%

The sum of the current income tax expense or benefit and the deferred income tax expense or benefit pertaining to continuing operations.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 9

-Subparagraph (a),(b)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32639-109319

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 109

-Paragraph 45

-Subparagraph a, 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(h))

-URI http://asc.fasb.org/extlink&oid=6881521&loc=d3e23780-122690

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 08

-Paragraph h

-Article 4

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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