Quarterly report pursuant to Section 13 or 15(d)

Marketable Securities Available-for-sale Securities (Details)

v3.7.0.1
Marketable Securities Available-for-sale Securities (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Mar. 26, 2017
Mar. 27, 2016
Mar. 26, 2017
Mar. 27, 2016
Sep. 25, 2016
Contractual maturities of available-for-sale debt securities [Abstract]          
Years to Maturity - Less Than One Year $ 6,979   $ 6,979    
Years to Maturity - One to Five Years 10,513   10,513    
Years to Maturity - Five to Ten Years 1,396   1,396    
Years to Maturity - Greater Than Ten Years 533   533    
Years to Maturity - No Single Maturity Date 2,067   2,067    
Realized Gains and Losses on Sales of Available-for-sale Securities [Abstract]          
Gross Realized Gains 57 $ 34 303 $ 84  
Gross Realized Losses 0 (11) (107) (22)  
Net Realized Gains 57 $ 23 196 $ 62  
Available-for-sale Securities [Abstract]          
Available-for-sale Equity Securities, Cost 171   171   $ 1,554
Available-for-sale Equity Securities, Unrealized Gains 75   75   204
Available-for-sale Equity Securities, Unrealized Losses 0   0   (12)
Available-for-sale Securities Equity Securities, Fair Value 246   246   1,746
Available-for-sale Debt Securities (including debt funds), Cost 21,360   21,360   24,363
Available-for-sale Debt Securities (including debt funds), Unrealized Gains 156   156   388
Available-for-sale Debt Securities (including debt funds), Unrealized Losses (28)   (28)   (93)
Available-for-sale Debt Securities, Fair Value 21,488   21,488   24,658
Available-for-sale Securities, Cost 21,531   21,531   25,917
Available-for-sale Securities, Unrealized Gains 231   231   592
Available-for-sale Securities, Unrealized Losses (28)   (28)   (105)
Fair Value 21,734   21,734   26,404
Investments Classified as Available-for-sale in a Continuous Unrealized Loss Position Deemed to be Temporary [Abstract]          
Less than 12 months - Fair Value 2,576   2,576   3,868
More than 12 months - Fair Value 83   83   1,699
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses (27)   (27)   (24)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses (1)   (1)   (81)
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 366   366   444
More than 12 months - Fair Value 3   3   16
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses (8)   (8)   (5)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses 0   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 2,141   2,141   2,775
More than 12 months - Fair Value 25   25   1,033
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses (18)   (18)   (12)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses 0   0   (65)
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 69   69   337
More than 12 months - Fair Value 55   55   211
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses (1)   (1)   (3)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses $ (1)   $ (1)   (2)
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
More than 12 months - Fair Value         130
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses         (4)
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses         (8)
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
More than 12 months - Fair Value         309
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Unrealized losses         0
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Unrealized losses         $ (6)