Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Millions, except Per Share data, unless otherwise specified	Mar. 31, 2012	Sep. 30, 2011	Apr. 02, 2011
Accounts receivable, allowances	$ 9.8	$ 12.9	$ 7.9
Property, plant and equipment, accumulated depreciation	$ 534.4	$ 510.5	$ 485.1
Common shares, stated value per share, US dollars per share	$ 0.01	$ 0.01	$ 0.01
Common shares, shares issued	61.1	60.8	65.7
Common shares, shares outstanding	61.1	60.8	65.7
Treasury shares, at cost, shares	7.1	7.5	2.6