Quarterly report pursuant to Section 13 or 15(d)

Composition of Certain Financial Statement Items Revenue recognition (Details)

v3.20.1
Composition of Certain Financial Statement Items Revenue recognition (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Mar. 29, 2020
Mar. 31, 2019
Mar. 29, 2020
Mar. 31, 2019
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Contract with Customer, Performance Obligation Satisfied in Previous Period $ 150 $ 398 $ 178 $ 394
Contract with Customer, Liability, Revenue Recognized     307 $ 258
Revenue, Remaining Performance Obligation, Amount 1,500   1,500  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-03-30        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 284   $ 284  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 6 months   6 months  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-09-28        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 511   $ 511  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year   1 year  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-09-27        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 463   $ 463  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year   1 year  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-09-26        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 202   $ 202  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year   1 year  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-09-25        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 50   $ 50  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year   1 year  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-09-30        
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]        
Revenue, Remaining Performance Obligation, Amount $ 26   $ 26  
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period 1 year   1 year