Derivative Financial Instruments - Additional Information (Details) - USD ($)	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014
Canadian Dollar Forward Contract
Derivative [Line Items]
Foreign currency forward contract to hedge	$ 4,000,000
Foreign currency forward contract term	90 days
Accrued unrealized foreign exchange loss	$ 18,000
Canadian Subsidiary
Derivative [Line Items]
Denominated intercompany accounts payable	28,100,000	$ 26,600,000
Denominated intercompany accounts payable, short-term nature	4,100,000
Denominated intercompany accounts payable, long-term nature	$ 24,000,000