Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2014

Mar. 31, 2013

Fair Value Disclosures [Abstract]

Fair Value Assets And Liabilities Measured On Recurring Basis

As of March 31, 2014 and 2013, our assets and liabilities that were measured and recorded at fair value on a recurring basis were as follows (in millions):

			Fair Value Measurements at Reporting Date Using
	As of March 31, 2014		Quoted Prices in Active Markets for Identical Financial Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs
			(Level 1)		(Level 2)		(Level 3)		Balance Sheet Classification
Assets
Money market funds	$	588	$	588	$	—	$	—	Cash equivalents
Available-for-sale securities:
Corporate bonds	279		—		279		—		Short-term investments
Commercial paper	146				146				Short-term investments and cash equivalents
U.S. Treasury securities	118		118		—		—		Short-term investments and cash equivalents
U.S. agency securities	89		—		89		—		Short-term investments and cash equivalents
Deferred compensation plan assets (a)	9		9		—		—		Other assets
Total assets at fair value	$	1,229	$	715	$	514	$	—
Liabilities
Contingent consideration (b)	$	4	$	—	$	—	$	4	Accrued and other current  liabilities and other liabilities
Foreign currency derivatives	6		—		6		—		Accrued and other current liabilities
Deferred compensation plan liabilities (a)	9		9		—		—		Other liabilities
Total liabilities at fair value	$	19	$	9	$	6	$	4

			Fair Value Measurements at Reporting Date Using
	As of March 31, 2013		Quoted Prices in Active Markets for Identical Financial Instruments		Significant Other Observable Inputs		Significant Unobservable Inputs
			(Level 1)		(Level 2)		(Level 3)		Balance Sheet Classification
Assets
Money market funds	$	469	$	469	$	—	$	—	Cash equivalents
Available-for-sale securities:
Corporate bonds	178		—		178		—		Short-term investments
U.S. agency securities	91		—		91		—		Short-term investments and cash equivalents
U.S. Treasury securities	88		88		—		—		Short-term investments and cash equivalents
Commercial paper	73		—		73		—		Short-term investments and cash equivalents
Deferred compensation plan assets (a)	11		11		—		—		Other assets
Foreign currency derivatives	6		—		6		—		Other current assets
Total assets at fair value	$	916	$	568	$	348	$	—
Liabilities
Contingent consideration (b)	$	43	$	—	$	—	$	43	Accrued and other current  liabilities and other liabilities
Deferred compensation plan liabilities (a)	12		12		—		—		Other liabilities
Total liabilities at fair value	$	55	$	12	$	—	$	43

Fair Value Measurements Using Significant Unobservable Inputs (Level 3)

	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
		Contingent Consideration
Balance as of March 31, 2013		$	43
Change in fair value (c)		(35		)
Payments (d)		(4		)
Balance as of March 31, 2014		$	4

	Fair Value Measurements Using Significant Unobservable Inputs (Level 3)
		Contingent Consideration
Balance as of March 31, 2012		$	112
Change in fair value (c)		(64		)
Payments (d)		(5		)
Balance as of March 31, 2013		$	43

Assets And Liabilities Measured At Fair Value On A Nonrecurring Basis

			Fair Value Measurements Using
	Net Carrying Value as of March 31, 2014		Quoted Prices in Active Markets  for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Total Impairments  for the Fiscal Year Ended March 31, 2014
			(Level 1)		(Level 2)		(Level 3)
Assets
Royalty-based asset	$	—	$	—	$	—	$	—	$	17
Total impairments recorded for non-recurring measurements on assets held as of March 31, 2014									$	17

			Fair Value Measurements Using
	Net Carrying Value as of March 31, 2013		Quoted Prices in Active Markets for Identical Assets		Significant Other Observable Inputs		Significant Unobservable Inputs		Total Impairments for the Fiscal Year Ended March 31, 2013
			(Level 1)		(Level 2)		(Level 3)
Assets
Acquisition-related intangible assets	$	4	$	—	$	—	$	4	$	39
Total impairments recorded for non-recurring measurements on assets held as of March 31, 2013									$	39