Employee Benefit Plans (Weighted Average Assumptions Used to Determine Net Periodic Benefit Cost for Defined Benefit Pension and Other Postretirement Plans) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		4.10%	3.80%
Discount rate		3.80%	4.60%	4.10%
Expected return on assets	7.25%	6.10%	6.50%	6.50%
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 26
Rate of compensation increase		2.00%	3.00%	4.00%
Pensions
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	27
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 16
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		4.50%	4.00%