Discontinued Operations - Summary Information (Details) - USD ($) $ in Millions	3 Months Ended							12 Months Ended
	Sep. 27, 2019	Jun. 28, 2019	Mar. 29, 2019	Dec. 28, 2018	Sep. 28, 2018	Jun. 29, 2018	Dec. 29, 2017	Sep. 27, 2019	Sep. 28, 2018	Sep. 29, 2017
Income (loss) from discontinued operations, net of income taxes
Net sales								$ 41	$ 702	$ 928
Cost of sales								50	602	653
Gross margin								(9)	100	275
Selling, general, and administrative expenses								11	48	50
Research, development, and engineering expenses								3	39	40
Restructuring and other charges (credits), net								3	30	(3)
Operating income (loss)								(26)	(17)	188
Non-operating income, net										22
Pre-tax income (loss) from discontinued operations								(26)	(17)	210
Pre-tax gain (loss) on sale of discontinued operations								(86)	(2)	3
Income tax (expense) benefit								10		(70)
Income (loss) from discontinued operations, net of income taxes	$ (4)	$ (1)	$ 10	$ (107)	$ (13)	$ 1	$ (7)	$ (102)	(19)	$ 143
Balance sheet information for assets and liabilities held for sale
Accounts receivable, net					72				72
Inventories					130				130
Other current assets					32				32
Property, plant, and equipment, net					221				221
Other assets					17				17
Total assets held for sale					472				472
Accounts payable					63				63
Accrued and other current liabilities					26				26
Deferred revenue					60				60
Other liabilities					39				39
Total liabilities held for sale					$ 188				$ 188