Postretirement Plans - Summary of Amounts Included in Accumulated Other Comprehensive Income on Accompanying Consolidated Balance Sheets (Parenthetical) (Detail) - USD ($) $ in Millions	Jan. 02, 2016	Jan. 03, 2015
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss), tax	$ 141.4	$ 134.9
U.S. Postretirement Health Care Plans [Member]
Defined Benefit Plan Disclosure [Line Items]
Net gain (loss), tax	$ 2.9	$ 1.5