Short-term Investments

3 Months Ended

Dec. 31, 2018

Investments Debt And Equity Securities [Abstract]

Short-term Investments

4.   Short-term Investments

	As of December 31, 2018 (in thousands)
	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Short-term investments:
Corporate bonds	$	6,289	$	—	$	(25	)	$	6,264
Government bonds		3,224		7		—			3,231
Total	$	9,513	$	7	$	(25	)	$	9,495

	As of September 30, 2018 (in thousands)
	Amortized Cost		Unrealized Gains		Unrealized Losses			Estimated Fair Value
Short-term investments:
Corporate bonds	$	17,851	$	—	$	(60	)	$	17,791
Government bonds		7,702		—		(22	)		7,680
Total	$	25,553	$	—	$	(82	)	$	25,471

The Company’s short-term investments have contractual maturities ranging from February 2019 to November 2020.