Commitments and Contingencies - Additional Information (Detail) $ in Millions	Jul. 01, 2017 USD ($)
Gain Contingencies [Line Items]
Purchase commitments	$ 879
Purchase commitments due in remainder of 2017	803
Purchase commitments due in 2018	76
Electricity [Member]
Gain Contingencies [Line Items]
Purchase commitments	6
Diesel Fuel [Member]
Gain Contingencies [Line Items]
Purchase commitments	68
Purchase commitments due in remainder of 2017	35
Purchase commitments due in 2018	$ 33