Employee Benefit Plans (Weighted Average Assumptions Used to Determine Benefit Obligation 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 Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Expected Long-term Return on Assets	7.25%	6.10%	6.50%	6.50%
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 26
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		4.10%	3.80%
Rate of compensation increase		2.00%	2.00%
Minimum
Defined Benefit Plan Disclosure [Line Items]
Estimated Decrease in Defined Benefit Expense	20
Maximum
Defined Benefit Plan Disclosure [Line Items]
Estimated Decrease in Defined Benefit Expense	25
Pensions
Defined Benefit Plan Disclosure [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	27
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Impact on Net Periodic Pension Expense - Next Twelve Months	$ 16
United States
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		4.50%	4.00%