(Fair Value Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended		12 Months Ended
	Sep. 30, 2014		Mar. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Weighted Average Discount Rate	17.00%		18.00%
Maximum potential payout of acquisition-related contingent consideration	$ 3		$ 10
Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets at fair value	827		1,229
Total liabilities at fair value	16		19
Quoted Prices In Active Markets For Identical Financial Instruments (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets at fair value	181		715
Total liabilities at fair value	10		9
Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets at fair value	646		514
Total liabilities at fair value	6		6
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets at fair value	0		0
Total liabilities at fair value	0		4
Cash Equivalents | Fair Value | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Cash equivalents	6		588
Cash Equivalents | Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) | Money market funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Cash equivalents	6		588
Short-Term Investments | Fair Value | Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	389		279
Short-Term Investments | Fair Value | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	165
Short-Term Investments | Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	165
Short-Term Investments | Significant Other Observable Inputs (Level 2) | Corporate bonds
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	389		279
Short-Term Investments And Cash Equivalents | Fair Value | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities			118
Short-Term Investments And Cash Equivalents | Fair Value | U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	146		89
Short-Term Investments And Cash Equivalents | Fair Value | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	99		146
Short-Term Investments And Cash Equivalents | Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) | U.S. Treasury securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities			118
Short-Term Investments And Cash Equivalents | Significant Other Observable Inputs (Level 2) | U.S. agency securities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	146		89
Short-Term Investments And Cash Equivalents | Significant Other Observable Inputs (Level 2) | Commercial paper
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Available-for-sale of securities	99		146
Other Current Assets | Fair Value | Foreign currency derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Foreign currency derivatives, assets	12
Other Current Assets | Significant Other Observable Inputs (Level 2) | Foreign currency derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Foreign currency derivatives, assets	12
Other assets | Fair Value | Deferred compensation plan assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Deferred compensation plan assets	10		9	[1]
Other assets | Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) | Deferred compensation plan assets
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Deferred compensation plan assets	10	[1]	9	[1]
Accrued and Other Current Liabilities | Fair Value | Foreign currency derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Foreign currency derivatives, liabilities	6		6
Accrued and Other Current Liabilities | Significant Other Observable Inputs (Level 2) | Foreign currency derivatives
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Foreign currency derivatives, liabilities	6		6
Other liabilities | Fair Value | Deferred Compensation Plan Liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Deferred compensation plan assets	10		9
Other liabilities | Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) | Deferred Compensation Plan Liabilities
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Deferred compensation plan assets	10		9
Accrued And Other Current Liabilities And Other Liabilities | Fair Value | Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Contingent consideration			4	[2]
Accrued And Other Current Liabilities And Other Liabilities | Fair Value, Inputs, Level 3 [Member] | Contingent consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Contingent consideration			$ 4	[2]

[1] The Deferred Compensation Plan assets consist of various mutual funds. See Note 15 in our Annual Report on Form 10-K for the fiscal year ended March 31, 2014, for additional information regarding our Deferred Compensation Plan.

[2] The immaterial contingent consideration as of September 30, 2014 represents the estimated fair value of the additional variable cash consideration payable in connection with our acquisition of KlickNation Corporation (“KlickNation”) that is contingent upon the achievement of certain performance milestones. The $4 million contingent consideration as of March 31, 2014 represents the estimated fair value of the additional variable cash consideration payable in connection with our acquisitions of KlickNation and Chillingo Limited (“Chillingo”) that are contingent upon the achievement of certain performance milestones. We estimated the fair value of the acquisition-related contingent consideration payable using probability-weighted discounted cash flow models, and applied a discount rate that appropriately captures the risk associated with the obligation. The weighted average of the discount rates used during the six months ended September 30, 2014 was 17 percent. The weighted average of the discount rates used during the fiscal year 2014 was 18 percent. The significant unobservable input used in the fair value measurement of the contingent consideration payable are forecasted earnings. Significant changes in forecasted earnings would result in a significantly higher or lower fair value measurement. At September 30, 2014 and March 31, 2014, the fair market value of acquisition-related contingent consideration was immaterial and $4 million, respectively, compared to a maximum potential payout of $3 million and $10 million, respectively.