Accounts Receivable and Finance Receivables (Details 6) (USD $) In Millions, unless otherwise specified	9 Months Ended
	Sep. 27, 2014	Sep. 28, 2013	Dec. 28, 2013
Finance receivables
Allowance based on collective evaluation	$ 33		$ 41
Allowance based on individual evaluation	23		14
Finance receivables evaluated collectively	1,077		1,226
Finance receivables evaluated individually	131		137
Allowance for losses
Balance at the beginning of period	55	84
Provision for losses	7	(23)
Charge-offs	(11)	(9)
Recoveries	5	11
Transfers		(1)
Balance at the end of period	$ 56	$ 62