Financial Instruments - Notional Amounts and Credit Risk Amounts Associated with Derivative Instruments (Details) - USD ($) $ in Millions	Mar. 28, 2020	Sep. 28, 2019
Derivatives designated as accounting hedges | Foreign exchange contracts
Derivative [Line Items]
Derivatives, notional amount	$ 59,198	$ 61,795
Derivatives, credit risk amount	2,803	1,798
Derivatives designated as accounting hedges | Interest rate contracts
Derivative [Line Items]
Derivatives, notional amount	27,350	31,250
Derivatives, credit risk amount	1,709	685
Derivatives not designated as accounting hedges | Foreign exchange contracts
Derivative [Line Items]
Derivatives, notional amount	91,165	76,868
Derivatives, credit risk amount	$ 1,425	$ 323