Fair Value Measurements (Tables)

12 Months Ended

Mar. 31, 2018

Fair Value Disclosures [Abstract]

Fair Value Assets And Liabilities Measured On Recurring Basis

			Fair Value Measurements at Reporting Date Using
	As of March 31, 2018		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
Bank and time deposits	$	286	$	286	$	—	$	—	Cash equivalents
Money market funds	1,876		1,876		—		—		Cash equivalents
Available-for-sale securities:
Corporate bonds	624		—		624		—		Short-term investments
U.S. Treasury securities	210		210		—		—		Short-term investments
U.S. agency securities	78		—		78		—		Short-term investments
Commercial paper	150		—		150		—		Short-term investments and cash equivalents
Foreign government securities	52		—		52		—		Short-term investments
Certificates of Deposit	2		—		2		—		Cash equivalents
Foreign currency derivatives	4		—		4		—		Other current assets and other assets
Deferred compensation plan assets (a)	10		10		—		—		Other assets
Total assets at fair value	$	3,292	$	2,382	$	910	$	—
Liabilities
Contingent consideration (b)	$	122	$	—	$	—	$	122	Other Liabilities
Foreign currency derivatives	56		—		56		—		Accrued and other current liabilities and other liabilities
Deferred compensation plan liabilities (a)	11		11		—		—		Other liabilities
Total liabilities at fair value	$	189	$	11	$	56	$	122

			Fair Value Measurements at Reporting Date Using
	As of March 31, 2017		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
Bank and time deposits	$	233	$	233	$	—	$	—	Cash equivalents
Money market funds	405		405		—		—		Cash equivalents
Available-for-sale securities:
Corporate bonds	963		—		963		—		Short-term investments and cash equivalents
U.S. Treasury securities	460		460		—		—		Short-term investments and cash equivalents
U.S. agency securities	172		—		172		—		Short-term investments and cash equivalents
Commercial paper	270		—		270		—		Short-term investments and cash equivalents
Foreign government securities	113		—		113		—		Short-term investments
Asset-backed securities	135		—		135		—		Short-term investments
Foreign currency derivatives	19		—		19		—		Other current assets and other assets
Deferred compensation plan assets (a)	8		8		—		—		Other assets
Total assets at fair value	$	2,778	$	1,106	$	1,672	$	—
Liabilities
Foreign currency derivatives	8		—		8		—		Accrued and other current liabilities and other liabilities
Deferred compensation plan liabilities (a)	9		9		—		—		Other liabilities
Total liabilities at fair value	$	17	$	9	$	8	$	—

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, 2017		$	—
Additions		122
Change in fair value		—
Balance as of March 31, 2018		$	122