Fair Value Measurements (Fair Value Of Assets And Liabilities Measured At Fair Value On A Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Mar. 31, 2012	Jun. 30, 2012 Fair Value	Mar. 31, 2012 Fair Value	Jun. 30, 2012 Quoted Prices In Active Markets For Identical Financial Instruments (Level 1)	Mar. 31, 2012 Quoted Prices In Active Markets For Identical Financial Instruments (Level 1)	Jun. 30, 2012 Significant Other Observable Inputs (Level 2)	Mar. 31, 2012 Significant Other Observable Inputs (Level 2)	Jun. 30, 2012 Significant Unobservable Inputs (Level 3)	Mar. 31, 2012 Significant Unobservable Inputs (Level 3)	Jun. 30, 2012 Significant Unobservable Inputs (Level 3) Contingent Consideration	Mar. 31, 2012 Significant Unobservable Inputs (Level 3) Contingent Consideration	Mar. 31, 2011 Significant Unobservable Inputs (Level 3) Contingent Consideration	Jun. 30, 2012 Cash Equivalents Fair Value Money Market Funds	Mar. 31, 2012 Cash Equivalents Fair Value Money Market Funds	Jun. 30, 2012 Cash Equivalents Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) Money Market Funds	Mar. 31, 2012 Cash Equivalents Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) Money Market Funds	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Fair Value Corporate bonds	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Fair Value U.S. Treasury securities	Mar. 31, 2012 Short-Term Investments And Cash Equivalents Fair Value U.S. Treasury securities	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Fair Value Commercial Paper	Mar. 31, 2012 Short-Term Investments And Cash Equivalents Fair Value Commercial Paper	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) U.S. Treasury securities	Mar. 31, 2012 Short-Term Investments And Cash Equivalents Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) U.S. Treasury securities	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Significant Other Observable Inputs (Level 2) Corporate bonds	Jun. 30, 2012 Short-Term Investments And Cash Equivalents Significant Other Observable Inputs (Level 2) Commercial Paper	Mar. 31, 2012 Short-Term Investments And Cash Equivalents Significant Other Observable Inputs (Level 2) Commercial Paper	Mar. 31, 2012 Short-Term Investments Fair Value Corporate bonds	Jun. 30, 2012 Short-Term Investments Fair Value U.S. agency securities	Mar. 31, 2012 Short-Term Investments Fair Value U.S. agency securities	Mar. 31, 2012 Short-Term Investments Significant Other Observable Inputs (Level 2) Corporate bonds	Jun. 30, 2012 Short-Term Investments Significant Other Observable Inputs (Level 2) U.S. agency securities	Mar. 31, 2012 Short-Term Investments Significant Other Observable Inputs (Level 2) U.S. agency securities	Jun. 30, 2012 Marketable Equity Securities Fair Value	Mar. 31, 2012 Marketable Equity Securities Fair Value	Jun. 30, 2012 Marketable Equity Securities Quoted Prices In Active Markets For Identical Financial Instruments (Level 1)	Mar. 31, 2012 Marketable Equity Securities Quoted Prices In Active Markets For Identical Financial Instruments (Level 1)	Jun. 30, 2012 Other Assets Fair Value Deferred Compensation Plan Assets		Mar. 31, 2012 Other Assets Fair Value Deferred Compensation Plan Assets		Jun. 30, 2012 Other Assets Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) Deferred Compensation Plan Assets		Mar. 31, 2012 Other Assets Quoted Prices In Active Markets For Identical Financial Instruments (Level 1) Deferred Compensation Plan Assets		Jun. 30, 2012 Other Current Assets Fair Value Foreign Currency Derivatives	Mar. 31, 2012 Other Current Assets Fair Value Foreign Currency Derivatives	Jun. 30, 2012 Other Current Assets Significant Other Observable Inputs (Level 2) Foreign Currency Derivatives	Mar. 31, 2012 Other Current Assets Significant Other Observable Inputs (Level 2) Foreign Currency Derivatives	Jun. 30, 2012 Accrued And Other Current Liabilities And Other Liabilities Fair Value Contingent Consideration		Mar. 31, 2012 Accrued And Other Current Liabilities And Other Liabilities Fair Value Contingent Consideration		Jun. 30, 2012 Accrued And Other Current Liabilities And Other Liabilities Significant Unobservable Inputs (Level 3) Contingent Consideration		Mar. 31, 2012 Accrued And Other Current Liabilities And Other Liabilities Significant Unobservable Inputs (Level 3) Contingent Consideration
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Fair value, Cash equivalents															$ 253	$ 490	$ 253	$ 490
Fair value, Available-for-sale of securities																			181	141	170	22	16	141	170	181	22	16	150	109	116	150	109	116	76	119	76	119
Fair value, Deferred compensation plan assets																																							11	[1]	11	[1]	11	[1]	11	[1]
Fair value, Foreign currency derivatives																																															4	2	4	2
Total assets at fair value				797	1,074	481	790	316	284
Fair value, Contingent consideration																																																			88	[2]	112	[2]	88	[2]	112	[2]
Total liabilities at fair value				88	112					88	112
Fair Value, Measurement with Unobservable Inputs Reconciliations, Recurring Basis, Liability Value												88	112	51
Impairment charges	0	0
Average Weighted Average Discount Rate	13.00%		12.00%
Business Acquisition, Contingent Consideration, Potential Cash Payment	$ 568		$ 572

[1] The deferred compensation plan assets consist of various mutual funds.

[2] The contingent consideration as of June 30, 2012 and March 31, 2012 represents the estimated fair value of the additional variable cash consideration payable primarily in connection with our acquisitions of PopCap Games, Inc. (“PopCap”), KlickNation Corporation (“KlickNation”), and Chillingo Limited (“Chillingo”) that is 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 a market participant's view of the risk associated with the obligation. During the three months ended June 30, 2012, the discount rate used had a weighted average of 13 percent. During fiscal year 2012, the discount rate used had a weighted average of 12 percent. The significant unobservable input used in the fair value measurement of the acquisition-related contingent consideration payable are forecasted earnings. Significant changes in forecasted earnings would result in a significantly higher or lower fair value measurement. At June 30, 2012 and March 31, 2012, the fair market value of acquisition-related contingent consideration totaled $88 million and $112 million, respectively, compared to a maximum potential payout of $568 million and $572 million, respectively.