Quarterly report pursuant to Section 13 or 15(d)

Marketable Securities Available-for-sale Securities (Details)

v2.4.0.6
Marketable Securities Available-for-sale Securities (Details) (USD $)
In Millions, unless otherwise specified
3 Months Ended 6 Months Ended
Mar. 31, 2013
Mar. 25, 2012
Mar. 31, 2013
Mar. 25, 2012
Sep. 30, 2012
Contractual maturities of available-for-sale debt securities [Abstract]          
Years to Maturity - Less Than One Year $ 776   $ 776    
Years to Maturity - One to Five Years 7,692   7,692    
Years to Maturity - Five to Ten Years 4,540   4,540    
Years to Maturity - Greater Than Ten Years 1,468   1,468    
Years to Maturity - No Single Maturity Date 6,787   6,787    
Total 21,263   21,263    
Realized Gains and Losses on Sales of Available-for-sale Securities [Abstract]          
Gross Realized Gains 69 64 153 100  
Gross Realized Losses (4) (4) (9) (6)  
Net Realized Gains 65 60 144 94  
Available-for-sale Securities [Abstract]          
Cost 23,342   23,342   20,313
Unrealized Gains 1,417   1,417   1,201
Unrealized Losses (32)   (32)   (33)
Fair Value 24,727   24,727   21,481
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 3,180   3,180   1,035
Less than 12 months - Unrealized Losses (28)   (28)   (18)
More than 12 months - Fair Value 193   193   423
More than 12 months - Unrealized Losses (4)   (4)   (15)
Equity securities [Member]
         
Available-for-sale Securities [Abstract]          
Cost 2,669   2,669   2,599
Unrealized Gains 800   800   628
Unrealized Losses (5)   (5)   (14)
Fair Value 3,464   3,464   3,213
Debt securities (including debt funds) [Member]
         
Available-for-sale Securities [Abstract]          
Cost 20,673   20,673   17,714
Unrealized Gains 617   617   573
Unrealized Losses (27)   (27)   (19)
Fair Value 21,263   21,263   18,268
Corporate bonds and notes [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 1,661   1,661   723
Less than 12 months - Unrealized Losses (8)   (8)   (8)
More than 12 months - Fair Value 83   83   256
More than 12 months - Unrealized Losses (3)   (3)   (9)
Mortgage- and asset-backed securities [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 220   220   143
Less than 12 months - Unrealized Losses (1)   (1)   (1)
More than 12 months - Fair Value 13   13   7
More than 12 months - Unrealized Losses 0   0   0
Auction rate securities [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 0   0   0
Less than 12 months - Unrealized Losses 0   0   0
More than 12 months - Fair Value 83   83   115
More than 12 months - Unrealized Losses (1)   (1)   (1)
Common and preferred stock [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 86   86   105
Less than 12 months - Unrealized Losses (5)   (5)   (5)
More than 12 months - Fair Value 10   10   9
More than 12 months - Unrealized Losses 0   0   0
Debt funds [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 1,213   1,213    
Less than 12 months - Unrealized Losses (14)   (14)    
More than 12 months - Fair Value 4   4    
More than 12 months - Unrealized Losses 0   0    
Equity funds [Member]
         
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value         64
Less than 12 months - Unrealized Losses         (4)
More than 12 months - Fair Value         36
More than 12 months - Unrealized Losses         $ (5)