Marketable Securities (Tables)

6 Months Ended

Mar. 31, 2017

Marketable Securities [Abstract]

Schedule of Marketable Securities

At March 31, 2017 our marketable securities were (in thousands):

	Amortized Cost (1)		Unrealized Gains		Unrealized Losses			Fair Value (1)
Current marketable securities:
Corporate bonds	$	25,360	$	—	$	(29	)	$	25,331
Commercial paper	5,988		—		(2		)	5,986
Certificates of deposit	4,757		7		—			4,764
Current marketable securities	36,105		7		(31		)	36,081
Non-current marketable securities:
Certificates of deposit	2,253		9		—			2,262
Total marketable securities	$	38,358	$	16	$	(31	)	$	38,343

(1) Included in amortized cost and fair value is purchased and accrued interest of $189.

At September 30, 2016 our marketable securities were (in thousands):

	Amortized Cost (1)		Unrealized Gains		Unrealized Losses			Fair Value (1)
Current marketable securities:
Corporate bonds	$	28,801	$	—	$	(34	)	$	28,767
Commercial paper	23,963		—		(20		)	23,943
Certificates of deposit	3,755		13		—			3,768
Government municipal bonds	1,904		—		—			1,904
Current marketable securities	58,423		13		(54		)	58,382
Non-current marketable securities:
Certificates of deposit	3,505		36		—			3,541
Total marketable securities	$	61,928	$	49	$	(54	)	$	61,923

(1) Included in amortized cost and fair value is purchased and accrued interest of $271.

Schedule of Unrealized Losses on Available-For-Sale Securities

The following tables show the fair values and gross unrealized losses of our available-for-sale marketable securities that have been in a continuous unrealized loss position deemed to be temporary, aggregated by investment category (in thousands):

	March 31, 2017
	Less than 12 Months					More than 12 Months
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate bonds	$	25,331	$	(29	)	$	—	$	—
Commercial paper	5,986		(2		)	—		—
Total	$	31,317	$	(31	)	$	—	$	—

	September 30, 2016
	Less than 12 Months					More than 12 Months
	Fair Value		Unrealized Losses			Fair Value		Unrealized Losses
Corporate bonds	$	24,454	$	(33	)	$	4,102	$	(1	)
Commercial paper	23,943		(20		)	—		—
Total	$	48,397	$	(53	)	$	4,102	$	(1	)