Operating segments and geographic area data (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2010	Jul. 31, 2010	Apr. 30, 2010	Jan. 31, 2010	Oct. 31, 2011	Oct. 31, 2010	Oct. 31, 2009
Net external sales
Net external sales	$ 331,018	$ 312,255	$ 318,924	$ 270,962	$ 290,182	$ 279,121	$ 251,659	$ 220,589	$ 1,233,159	$ 1,041,551	$ 819,165
Long-lived assets
Long-lived assets	130,883				116,395				130,883	116,395	118,291
United States [Member]
Net external sales
Net external sales									312,328	273,652	234,038
Long-lived assets
Long-lived assets	90,994				80,974				90,994	80,974	79,675
Americas [Member]
Net external sales
Net external sales									102,077	78,058	60,632
Long-lived assets
Long-lived assets	2,933				1,865				2,933	1,865	1,703
Europe [Member]
Net external sales
Net external sales									390,319	336,119	294,951
Long-lived assets
Long-lived assets	16,312				13,401				16,312	13,401	15,329
Japan [Member]
Net external sales
Net external sales									111,003	93,318	81,678
Long-lived assets
Long-lived assets	3,496				3,587				3,496	3,587	3,257
Asia Pacific [Member]
Net external sales
Net external sales									317,432	260,404	147,866
Long-lived assets
Long-lived assets	$ 17,148				$ 16,568				$ 17,148	$ 16,568	$ 18,327