Schedule of Assumptions Used to Determine Benefit Obligations and Net Periodic Benefit Cost (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumptions used to determine benefit obligations, Discount rate	4.50%	4.00%
Assumptions used to determine benefit obligations, Rate of compensation increase	3.10%	3.80%
Assumptions used to determine net periodic benefit cost, Discount rate	4.00%	5.00%
Assumptions used to determine net periodic benefit cost, Expected return on plan assets	8.20%	8.20%
Assumptions used to determine net periodic benefit cost, Rate of compensation increases	3.80%	3.90%
Other Benefits
Defined Benefit Plan Disclosure [Line Items]
Assumptions used to determine benefit obligations, Discount rate	4.60%	3.80%
Assumptions used to determine benefit obligations, Rate of compensation increase	0.00%	0.00%
Assumptions used to determine net periodic benefit cost, Discount rate	3.80%	4.80%
Assumptions used to determine net periodic benefit cost, Expected return on plan assets	0.00%	0.00%
Assumptions used to determine net periodic benefit cost, Rate of compensation increases	0.00%	0.00%