Derivative Financial Instruments - Additional Information (Details) - USD ($)	9 Months Ended
	Jun. 30, 2015	Sep. 30, 2014
Canadian Dollar Forward Contract
Derivative Financial Instruments [Line Items]
Foreign currency forward contract to hedge	$ 3,000,000
Foreign currency forward contract term	90 days
Accrued unrealized foreign exchange gain	$ 28,000
Canadian Subsidiary
Derivative Financial Instruments [Line Items]
Denominated intercompany accounts payable	27,700,000	$ 29,800,000
Canadian Subsidiary | Short-term nature
Derivative Financial Instruments [Line Items]
Denominated intercompany accounts payable	3,100,000
Canadian Subsidiary | Long-term nature
Derivative Financial Instruments [Line Items]
Denominated intercompany accounts payable	$ 24,600,000