Derivative Financial Instruments (Tables)

12 Months Ended

Sep. 30, 2016

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Schedule of Notional Amounts of Outstanding Derivative Positions

The following tables summarize our outstanding foreign currency forward contracts, by currency at September 30, 2016 and 2015:

		September 30, 2016
	Contract Amount				Fair Value
	Foreign Currency		US$		US$
		(In thousands)
Sell foreign currency:
Euro (EUR)	EUR	7,850	$	8,743	—
Buy foreign currency:
British pound (GBP)	GBP	7,721	$	10,000	—

		September 30, 2015
	Contract Amount				Fair Value
	Foreign Currency		US$		US$
		(In thousands)
Sell foreign currency:
Canadian dollar (CAD)	CAD	2,750	$	2,045	$	—
Euro (EUR)	EUR	5,600	$	6,296	—
Buy foreign currency:
British pound (GBP)	GBP	6,943	$	10,550	—

Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance

These amounts are shown below for the years ended September 30, 2016, 2015 and 2014:

	Year Ended September 30,
	2016			2015			2014
	(In thousands)
Gain (loss) on foreign currency forward contracts	$	(2,911	)	$	(62	)	$	256