Financial Instruments (Schedule Of Financial Instruments Measured And Recorded At Fair Value On Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Financial Instrument [Line Items]
Cash equivalents	$ 1,042	$ 739
Marketable securities	351	896
Long-term marketable securities	169	149
Other assets	10	10
Prepaid expenses and other current assets	1
Total assets measured at fair value	1,573	1,794
Total liabilities measured at fair value		(2)
Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Financial Instrument [Line Items]
Cash equivalents	917	738
Long-term marketable securities	1	9
Other assets	10	10
Total assets measured at fair value	928	757
Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Cash equivalents	125	1
Marketable securities	319	858
Long-term marketable securities	168	140
Prepaid expenses and other current assets	1
Total assets measured at fair value	613	999
Total liabilities measured at fair value		(2)
Significant Unobservable Inputs (Level 3) [Member]
Financial Instrument [Line Items]
Marketable securities	32	38
Total assets measured at fair value	32	38
Money Market Funds [Member]
Financial Instrument [Line Items]
Cash equivalents	917	738
Long-term marketable securities	1	9
Other assets	10	10
Money Market Funds [Member] | Quoted Prices In Active Markets For Identical Assets (Level 1) [Member]
Financial Instrument [Line Items]
Cash equivalents	917	738
Long-term marketable securities	1	9
Other assets	10	10
Money Market Funds [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Long-term marketable securities		0
Commercial Paper [Member]
Financial Instrument [Line Items]
Cash equivalents	125	1
Marketable securities	249	698
Commercial Paper [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Cash equivalents	125	1
Marketable securities	249	698
Time Deposits [Member]
Financial Instrument [Line Items]
Marketable securities	70	160
Time Deposits [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Marketable securities	70	160
Auction Rate Securities [Member]
Financial Instrument [Line Items]
Marketable securities	32	38
Auction Rate Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial Instrument [Line Items]
Marketable securities	32	38
Corporate Bonds [Member]
Financial Instrument [Line Items]
Long-term marketable securities	168	140
Corporate Bonds [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Long-term marketable securities	168	140
Foreign Currency Derivative Contracts [Member]
Financial Instrument [Line Items]
Prepaid expenses and other current assets	1
Total liabilities measured at fair value		(2)
Foreign Currency Derivative Contracts [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Instrument [Line Items]
Prepaid expenses and other current assets	1
Total liabilities measured at fair value		$ (2)