Income Tax Returns to be Reviewed (Detail)	12 Months Ended
	Dec. 31, 2012
UNITED STATES
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2000 - Present
CANADA
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2006 - Present
UNITED KINGDOM
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2009 - Present
CHINA
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2009 - Present
JAPAN
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2007 - Present
GERMANY
Income Tax Examination [Line Items]
Income tax returns to be reviewed	2006 - Present