Contingencies - Additional Information (Detail) - RTI Technologies - USD ($) $ in Millions			3 Months Ended	12 Months Ended
	Jan. 15, 2015	Sep. 19, 2013	Sep. 30, 2013	Sep. 30, 2015
Loss Contingencies [Line Items]
Damages awarded	$ 341.0	$ 113.5		$ 5.0
Pre-tax charge relating to an unfavorable litigation verdict			$ 341.0
Professional fees	$ 12.0