Derivative Financial Instruments (Tables)

6 Months Ended

Mar. 31, 2021

Derivative Instruments and Hedging Activities Disclosure [Abstract]

Summary of Outstanding Foreign Currency Forward Contracts

The following tables summarize our outstanding foreign currency forward contracts, by currency, at March 31, 2021 and September 30, 2020:

	March 31, 2021
	Contract Amount				Fair Value
	Foreign Currency		USD		USD
	(In thousands)
Sell foreign currency:
Euro (EUR)	EUR	19,200	$	22,643	$	—
Buy foreign currency:
British pound (GBP)	GBP	14,780	$	20,400	$	—
Singapore dollar (SGD)	SGD	5,790	$	4,300	$	—

	September 30, 2020
	Contract Amount				Fair Value
	Foreign Currency		USD		USD
	(In thousands)
Sell foreign currency:
Euro (EUR)	EUR	15,000	$	17,656	$	—
Buy foreign currency:
British pound (GBP)	GBP	16,555	$	21,300	$	—
Singapore dollar (SGD)	SGD	7,815	$	5,700	$	—

Losses on Derivative Financial Instruments

Gains (losses) on derivative financial instruments were recorded in our condensed consolidated statements of income and comprehensive income as a component of other income (expense), net, and consisted of the following: 

	Quarter Ended March 31,				Six Months Ended March 31,
	2021		2020		2021		2020
	(In thousands)
Gains (losses) on foreign currency forward contracts	$	1,229	$	(2,194)	$	2,915	$	(1,049)