Annual report pursuant to Section 13 and 15(d)

Marketable Securities Available-for-sale Securities (Details)

v3.3.0.814
Marketable Securities Available-for-sale Securities (Details) - USD ($)
$ in Millions
 12 Months Ended
Sep. 27, 2015
Sep. 28, 2014
Sep. 29, 2013
Contractual maturities of available-for-sale debt securities [Abstract]      
Years to Maturity - Less Than One Year $ 3,124    
Years to Maturity - One to Five Years 11,271    
Years to Maturity - Five to Ten Years 980    
Years to Maturity - Greater Than Ten Years 510    
Years to Maturity - No Single Maturity Date 4,474    
Realized Gains and Losses on Sales of Available-for-sale Securities [Abstract]      
Gross Realized Gains 540 $ 732 $ 430
Gross Realized Losses (52) (18) (142)
Net Realized Gains 488 714 $ 288
Available-for-sale Securities [Abstract]      
Available-for-sale Equity Securities, Amortized Cost Basis 1,394 1,769  
Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax 264 575  
Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax (28) (6)  
Available-for-sale Securities Equity Securities, Fair Value 1,630 2,338  
Available-for-sale Debt Securities (including debt funds), Amortized Cost Basis 20,459 19,582  
Available-for-sale Debt Securities (including debt funds), Accumulated Gross Unrealized Gain, before Tax 185 312  
Available-for-sale Debt Securities (including debt funds), Accumulated Gross Unrealized Loss, before Tax (285) (60)  
Available-for-sale Debt Securities, Fair Value 20,359 19,834  
Cost 21,853 21,351  
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 449 887  
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (313) (66)  
Fair Value 21,989 22,172  
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]      
Less than 12 months - Fair Value 11,006 5,906  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (245) (38)  
More than 12 months - Fair Value 617 675  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (68) (28)  
U.S. Treasury securities and government-related 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 304 279  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (4) (2)  
More than 12 months - Fair Value 0 0  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 0  
Corporate bonds and notes      
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]      
Less than 12 months - Fair Value 7,656 4,924  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (93) (31)  
More than 12 months - Fair Value 368 104  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (62) (4)  
Mortgage- and asset-backed and 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 862 484  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (3) (1)  
More than 12 months - Fair Value 108 135  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (1) (2)  
Equity and preferred securities and equity funds      
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]      
Less than 12 months - Fair Value 392 86  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (28) (3)  
More than 12 months - Fair Value 17 52  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 (3)  
Debt funds      
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]      
Less than 12 months - Fair Value 1,792 133  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (117) (1)  
More than 12 months - Fair Value 124 384  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss $ (5) $ (19)