Summary Of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Jul. 05, 2015	Jun. 29, 2014	Jul. 05, 2015	Jun. 29, 2014
Accounting Policies [Abstract]
Length of fiscal quarters, weeks			91 days
Net increase in operating earnings from the quarterly impact of revisions in contract	$ 45	$ 62	$ 108	$ 100
Net increase in operating earnings per share from the quarterly impact of revisions in contract	$ 0.09	$ 0.12	$ 0.21	$ 0.19