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Stockholders' Equity and Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended		21 Months Ended
	Sep. 28, 2019	Jun. 29, 2019	Mar. 30, 2019	Sep. 29, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Dec. 31, 2018
Stockholders' Equity and Accumulated Other Comprehensive Loss
Stock repurchase programs, authorized amount	$ 78						$ 78		$ 78
Common shares repurchased (in shares)							4,369
Repurchase of common stock	3	$ 1	$ 13				$ 17
Changes in the components of other comprehensive loss (OCL), net of related taxes
Foreign currency translation adjustment	2			$ (25)			(9)	$ (52)
Unrecognized pension cost	1			1			7	(1)
Other comprehensive income (loss), net of tax	3	$ (6)	$ 1	(24)	$ (20)	$ (9)	(2)	(53)
Components of accumulated other comprehensive loss, net of related taxes
Accumulated other comprehensive loss	(412)						(412)		(412)	$ (410)
Certain subsidiaries
Components of accumulated other comprehensive loss, net of related taxes
Unrecognized pension cost related to employees at certain subsidiaries	20			$ 23			20	$ 23	20
Tax benefit recorded on unrecognized pension cost							0
Foreign currency translation adjustment
Components of accumulated other comprehensive loss, net of related taxes
Accumulated other comprehensive loss	(358)						(358)		(358)	(349)
Unrecognized pension cost
Components of accumulated other comprehensive loss, net of related taxes
Accumulated other comprehensive loss	$ (54)						$ (54)		$ (54)	$ (61)
Effective income tax rate (as a percent)									26.00%