Unrecognized Tax Benefit Reconciliation (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 28, 2012
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit at beginning of year	$ 34	$ 29	$ 39
Change attributable to withdrawal of tax positions previously taken or expected to be taken			12
Change attributable to tax positions taken during the current period			(20)
Change attributable to tax positions taken during the current period	3	8
Decrease attributable to settlements with taxing authorities	(27)	(2)
Decrease attributable to lapse of statute of limitations	0	(1)	(2)
Unrecognized tax benefit at end of year	$ 10	$ 34	$ 29