Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash Reported in the Consolidated Balance Sheet that sum to the Total Amount in the Statement of Cash Flow (Details) - USD ($) $ in Millions	Sep. 30, 2017	Oct. 01, 2016	Oct. 03, 2015	Sep. 27, 2014
Accounting Policies [Abstract]
Cash and cash equivalents	$ 4,017	$ 4,610	$ 4,269
Restricted Cash and Investments, Current	26	96	250
Restricted Cash and Investments, Noncurrent	21	54	206
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 4,064	$ 4,760	$ 4,725	$ 3,688