Fair Value of Financial Instruments (Tables)

3 Months Ended

Dec. 31, 2017

Fair Value Disclosures [Abstract]

Fair Value Measurement of Company's Short-term Investments and Derivative Instruments

The fair value measurement of the Company’s short-term investments and derivative instruments was determined using the following inputs (in thousands):

	As of December 31, 2017
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable (Level 2)		Significant Unobservable (Level 3)		Totals
Short-term investments
Corporate bonds	$	23,711	$	—	$	—	$	23,711
Government bonds		12,750		—		—		12,750
Total	$	36,461	$	—	$	—	$	36,461

	As of September 30, 2017
	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable (Level 2)		Significant Unobservable (Level 3)		Totals
Short-term investments
Corporate bonds	$	22,798	$	—	$	—	$	22,798
Government bonds		13,339		—		—	$	13,339
Total	$	36,137	$	—	$	—	$	36,137