Operations and summary of significant accounting policies (Schedule of property, plant, and equipment useful lives) (Details)	12 Months Ended
	Sep. 30, 2011 years
Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life, Minimum	1
Property, Plant and Equipment, Useful Life, Maximum	40
Building and Building Improvements [Member]
Property, Plant and Equipment, Useful Life, Minimum	2
Property, Plant and Equipment, Useful Life, Maximum	40
Machinery and Equipment [Member]
Property, Plant and Equipment, Useful Life, Minimum	2
Property, Plant and Equipment, Useful Life, Maximum	15
Computer Equipment and Software [Member]
Property, Plant and Equipment, Useful Life, Minimum	3
Property, Plant and Equipment, Useful Life, Maximum	10
Other Capitalized Property Plant and Equipment [Member]
Property, Plant and Equipment, Useful Life, Minimum	2
Property, Plant and Equipment, Useful Life, Maximum	20