Assumptions Used to Determine Projected and Accumulated Benefit Obligations of Domestic Defined Benefit Pension and Postretirement Benefit Plans (Detail)	Dec. 31, 2013	Dec. 31, 2012
Defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.70%	4.00%
Weighted average rate of future compensation increases	3.80%	3.80%
Postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.70%	4.00%
Annual increase in Medicare Part B premium	6.00%	6.00%
Projected and Accumulated Benefit Obligations | Pre-65
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate	8.50%	8.50%
Ultimate cost trend rate	6.10%	6.10%
Year that the rate reaches the ultimate cost trend rate	2030	2030
Projected and Accumulated Benefit Obligations | Post-65
Defined Benefit Plan Disclosure [Line Items]
Health care cost trend rate	7.50%	7.50%
Ultimate cost trend rate	5.40%	5.40%
Year that the rate reaches the ultimate cost trend rate	2030	2030