Tax Year Returns that Remain Subject to Examination by Major Tax Jurisdiction (Detail)	9 Months Ended
	Sep. 30, 2012
Australia | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2008
Australia | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011
Canada | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2008
Canada | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011
France | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2009
France | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011
Japan | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2010
Japan | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011
Switzerland
Income Tax Examination [Line Items]
Open Tax Years	2011
United Kingdom | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2009
United Kingdom | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011
United States | Minimum
Income Tax Examination [Line Items]
Open Tax Years	2009
United States | Maximum
Income Tax Examination [Line Items]
Open Tax Years	2011