Financial Instruments (Tables)

3 Months Ended

Sep. 30, 2016

Financial Instruments

Summary of amortized cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category for cash, cash equivalents and short-term investments

The following tables summarize the amortized cost, gross unrealized gains, gross unrealized losses and fair value by significant investment category for cash, cash equivalents and short-term investments (in thousands):

	September 30, 2016
								Estimated Market Value
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Cash and Cash Equivalents		Short-term Investments
Cash	$	80,266	$	—	$	—		$	80,266	$	—
Level 1
Money market funds	3,350		—		—			3,350		—
	3,350		—		—			3,350		—
Level 2
U.S. agency securities	34,993		5		(22		)	—		34,976
U.S. treasury bills	2,000		—		—			—		2,000
Corporate notes	3,830		1		(1		)	—		3,830
	40,823		6		(23		)	—		40,806
Total	$	124,439	$	6	$	(23	)	$	83,616	$	40,806

	June 30, 2016
								Estimated Market Value
	Amortized Cost		Gross Unrealized Gains		Gross Unrealized Losses			Cash and Cash Equivalents		Short-term Investments
Cash	$	95,906	$	—	$	—		$	95,906	$	—
Level 1
Money market funds	13,362		—		—			13,362		—
	13,362		—		—			13,362		—
Level 2
Commercial paper	14,704		—		—			8,938		5,766
U.S. government agency securities	28,000		7		(17		)	—		27,990
U.S. Treasury securities	3,997		1		—			—		3,998
Municipal debt securities	1,565		—		—			1,565		—
Corporate debt securities	9,491		—		(6		)	—		9,485
	57,757		8		(23		)	10,503		47,239
Total	$	167,025	$	8	$	(23	)	$	119,771	$	47,239

Schedule of contractual maturities of available-for-sale securities

Contractual maturities of available-for-sale securities at September 30, 2016 were as follows (in thousands):

	September 30, 2016
	Amortized Cost		Fair Value
Due in 1 year or less	$	12,181	$	12,182
Due in 1-2 years	31,992		31,974
	$	44,173	$	44,156

Schedule of available-for-sale debt securities that were in a continuous unrealized loss position

	Less Than 12 Months					12 Months or Greater					Total
(in thousands)	Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value		Gross Unrealized Losses			Estimated Fair Value
September 30, 2016
Debt securities:
Corporate debt securities	$	(1	)	$	3,830	—			—		$	(1	)	$	3,830
U.S. government agencies securities	—			—		(22		)	31,974		(22		)	31,974
Total	$	(1	)	$	3,830	$	(22	)	$	31,974	$	(23	)	$	35,804
June 30, 2016
Debt securities:
Corporate debt securities	$	(3	)	$	6,325	$	(3	)	$	3,160	$	(6	)	$	9,485
U.S. government agencies securities	—			—		(17		)	19,988		(17		)	19,988
Total	$	(3	)	$	6,325	$	(20	)	$	23,148	$	(23	)	$	29,473

Summary of carrying values and estimated fair values of short-term and long-term debt

The following table summarizes the carrying values and estimated fair values of our short-term and long-term debt (in thousands):

	September 30, 2016				June 30, 2016
	Carrying Value		Fair Value		Carrying Value		Fair Value
3.75% Convertible Notes	$	—	$	—	$	36,400	$	36,487
3.50% Convertible Notes	43,417		58,397		43,195		51,450
3.50% Series A Convertible Notes	67,178		91,996		66,613		81,053
Secured Loan	64,429		64,429		64,204		64,204
Total	$	175,024	$	214,822	$	210,412	$	233,194