Pension and Other Benefit Plans - Weighted-Average Allocation of Plan Assets and Target Allocation by Asset Category (Detail)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
US Plan Assets [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Total	100.00%
Target allocation of assets	100.00%	100.00%
US Plan Assets [Member] | Equity securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	45.00%
Target Allocation Percentage of Assets, Range Maximum	55.00%
Target allocation of assets	47.00%	47.00%
US Plan Assets [Member] | Debt securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	33.00%
Target Allocation Percentage of Assets, Range Maximum	45.00%
Target allocation of assets	42.00%	39.00%
US Plan Assets [Member] | Cash and cash equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	0.00%
Target Allocation Percentage of Assets, Range Maximum	3.00%
Target allocation of assets	2.00%	6.00%
US Plan Assets [Member] | Alternative investments [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	0.00%
Target Allocation Percentage of Assets, Range Maximum	10.00%
Target allocation of assets	9.00%	8.00%
International [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Total	100.00%
Target allocation of assets	100.00%	100.00%
International [Member] | Equity securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	50.00%
Target Allocation Percentage of Assets, Range Maximum	70.00%
Target allocation of assets	56.00%	51.00%
International [Member] | Debt securities [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	25.00%
Target Allocation Percentage of Assets, Range Maximum	40.00%
Target allocation of assets	35.00%	38.00%
International [Member] | Cash and cash equivalents [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	0.00%
Target Allocation Percentage of Assets, Range Maximum	3.00%
Target allocation of assets	3.00%	4.00%
International [Member] | Alternative investments [Member]
Pension Plans, Postretirement and Other Employee Benefits [Line Items]
Target Allocation Percentage of Assets, Range Minimum	0.00%
Target Allocation Percentage of Assets, Range Maximum	20.00%
Target allocation of assets	6.00%	7.00%