Pension and Other Benefit Programs - Defined Benefit Plan Assets Measured at Fair Value (Detail) - USD ($) $ in Millions		Sep. 30, 2017	Oct. 01, 2016
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 6,943	$ 6,158
Fair value asset measurements		$ 13,021	$ 11,015
Percentage of plan assets mix		100.00%	100.00%
Cash
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 88	$ 115
Percentage of plan assets mix		1.00%	1.00%
Equity Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy	[1]	$ 2,974	$ 2,238
Percentage of plan assets mix	[1]	23.00%	20.00%
Mutual Funds
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 771	$ 720
Percentage of plan assets mix		6.00%	7.00%
US Government Debt Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 2,418	$ 2,536
Percentage of plan assets mix		19.00%	23.00%
Corporate Bond Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 579	$ 469
Percentage of plan assets mix		4.00%	4.00%
Collateralized Mortgage Backed Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 99	$ 86
Percentage of plan assets mix		1.00%	1.00%
Derivatives and Other, Net
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 14	$ (6)
Percentage of plan assets mix		0.00%	0.00%
Common Collective Funds
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Fair value asset measurements		$ 2,727	$ 1,861
Percentage of plan assets mix		21.00%	17.00%
Alternative Investments Funds
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Fair value asset measurements		$ 2,201	$ 2,072
Percentage of plan assets mix		17.00%	19.00%
Money Market Funds and Other
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Fair value asset measurements		$ 1,150	$ 924
Percentage of plan assets mix		9.00%	8.00%
Level 1
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 5,703	$ 5,190
Level 1 | Cash
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		88	115
Level 1 | Equity Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy	[1]	2,974	2,238
Level 1 | Mutual Funds
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		771	720
Level 1 | US Government Debt Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		1,870	2,116
Level 1 | Corporate Bond Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		0	0
Level 1 | Collateralized Mortgage Backed Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		0	0
Level 1 | Derivatives and Other, Net
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		0	1
Level 2
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		1,240	968
Level 2 | Cash
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		0	0
Level 2 | Equity Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy	[1]	0	0
Level 2 | Mutual Funds
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		0	0
Level 2 | US Government Debt Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		548	420
Level 2 | Corporate Bond Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		579	469
Level 2 | Collateralized Mortgage Backed Securities
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		99	86
Level 2 | Derivatives and Other, Net
Schedule of Pension and Other Postretirement Benefits Changes in Benefit Obligation and Fair Value of Plan Assets [Line Items]
Investments in the Fair Value Hierarchy		$ 14	$ (7)

[1] Includes 2.9 million shares of Company common stock valued at $282 million (2% of total plan assets) and 2.8 million shares valued at $264 million (2% of total plan assets) at September 30, 2017 and October 1, 2016, respectively.