Operations and summary of significant accounting policies (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Basis of Presentation
Selling, general, and administrative expenses include net foreign currency transaction gains (losses)		$ (1,721)	$ (1,089)	$ (2,738)
Goodwill, Impairment Loss		0	0	0
Asset Impairment Charges	$ 3,138	$ 0	$ 3,138	$ 0