Annual report pursuant to Section 13 and 15(d)

Marketable Securities Available-for-sale Securities (Details)

v3.5.0.2
Marketable Securities Available-for-sale Securities (Details) - USD ($)
$ in Millions
 12 Months Ended
Sep. 25, 2016
Sep. 27, 2015
Sep. 28, 2014
Contractual maturities of available-for-sale debt securities [Abstract]      
Years to Maturity - Less Than One Year $ 4,892    
Years to Maturity - One to Five Years 12,819    
Years to Maturity - Five to Ten Years 2,269    
Years to Maturity - Greater Than Ten Years 978    
Years to Maturity - No Single Maturity Date 3,700    
Realized Gains and Losses on Sales of Available-for-sale Securities [Abstract]      
Gross Realized Gains 277 $ 540 $ 732
Gross Realized Losses (37) (52) (18)
Net Realized Gains 240 488 $ 714
Available-for-sale Securities [Abstract]      
Available-for-sale Equity Securities, Amortized Cost Basis 1,554 1,394  
Available-for-sale Equity Securities, Accumulated Gross Unrealized Gain, before Tax 204 264  
Available-for-sale Equity Securities, Accumulated Gross Unrealized Loss, before Tax (12) (28)  
Available-for-sale Securities Equity Securities, Fair Value 1,746 1,630  
Available-for-sale Debt Securities (including debt funds), Amortized Cost Basis 24,363 20,459  
Available-for-sale Debt Securities (including debt funds), Accumulated Gross Unrealized Gain, before Tax 388 185  
Available-for-sale Debt Securities (including debt funds), Accumulated Gross Unrealized Loss, before Tax (93) (285)  
Available-for-sale Debt Securities, Fair Value 24,658 20,359  
Cost 25,917 21,853  
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax 592 449  
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax (105) (313)  
Fair Value 26,404 21,989  
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]      
Less than 12 months - Fair Value 3,868 11,006  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (24) (245)  
More than 12 months - Fair Value 1,699 617  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (81) (68)  
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 444 304  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (5) (4)  
More than 12 months - Fair Value 16 0  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss 0 0  
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 2,775 7,656  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (12) (93)  
More than 12 months - Fair Value 1,033 368  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (65) (62)  
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 337 862  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (3) (3)  
More than 12 months - Fair Value 211 108  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (2) (1)  
Equity and preferred securities and 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 312 392  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss (4) (28)  
More than 12 months - Fair Value 130 17  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss (8) 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 0 1,792  
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Accumulated Loss 0 (117)  
More than 12 months - Fair Value 309 124  
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Accumulated Loss $ (6) $ (5)