Subsidiaries Remain Subject to Tax Examination (Detail)	6 Months Ended
	Apr. 30, 2013
United States - Synopsys
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal 2012
United States - Magma Design Automation
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal years after 2009
California - Synopsys
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal years after 2007
California - Magma Design Automation
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal years after 2008
Hungary
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal years after 2006
Taiwan, Ireland and Japan
Income Tax Examination [Line Items]
Year(s) Subject to Examination	Fiscal years after 2007