Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Sep. 30, 2014
Other Liabilities
Net accrued retirement benefits, less amounts recognized within accrued liabilities	$ 55,259	$ 38,850
Total unrecognized tax benefits, net of offsetting adjustments	15,394	14,707
Acquired performance obligations and unfavorable contracts	4,656	12,792
Deferred economic incentives	19,163	18,408
Other	21,718	16,454
Other liabilities	$ 116,190	$ 101,211