Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Jun. 30, 2015	Sep. 30, 2014	Jun. 30, 2014
Cash, cash equivalents and short-term investments
Cash	$ 84,458	$ 73,444
Cash Equivalents		73,444
Amortized Cost	67,551
Gross Unrealized Gains	9	6
Gross Unrealized Losses	(47)	(83)
Available-for-sale Securities	67,513
Total Amortized Cost	153,135	143,934
Cash and Cash Equivalents	85,584	79,551	$ 107,295	$ 92,346
Short-term investments	67,513	64,306
Amortized Cost
Due in 1 year or less	55,551
Due in 1-2 years	12,000
Amortized cost	67,551
Fair Value
Due in 1 year or less	55,529
Due in 1-2 years	11,984
Available-for-sale Securities	67,513
Level 1
Cash, cash equivalents and short-term investments
Cash Equivalents	1,126
Cash Equivalents and Short-term Investments including Available-for-sale Securities	1,126
Level 1 | Money market funds
Cash, cash equivalents and short-term investments
Cash Equivalents	1,126	6,107
Cash Equivalents and Short-term Investments including Available-for-sale Securities	1,126	6,107
Amortized Cost		6,107
Amortized Cost
Amortized cost		6,107
Level 2
Cash, cash equivalents and short-term investments
Amortized Cost	67,551	64,383
Gross Unrealized Gains	9	6
Gross Unrealized Losses	(47)	(83)
Short-term investments	67,513	64,306
Amortized Cost
Amortized cost	67,551	64,383
Level 2 | Commercial paper
Cash, cash equivalents and short-term investments
Amortized Cost	11,991	11,989
Short-term investments	11,991	11,989
Amortized Cost
Amortized cost	11,991	11,989
Level 2 | Agency Securities [Member]
Cash, cash equivalents and short-term investments
Amortized Cost	25,000	21,999
Gross Unrealized Gains	6	6
Gross Unrealized Losses	(2)	(14)
Short-term investments	25,004	21,991
Amortized Cost
Amortized cost	25,000	21,999
Level 2 | Non-U.S. government securities
Cash, cash equivalents and short-term investments
Amortized Cost	1,500	1,504
Gross Unrealized Losses		(3)
Short-term investments	1,500	1,501
Amortized Cost
Amortized cost	1,500	1,504
Level 2 | Corporate notes
Cash, cash equivalents and short-term investments
Amortized Cost	29,060	28,891
Gross Unrealized Gains	3
Gross Unrealized Losses	(45)	(66)
Available-for-sale Securities	29,018
Short-term investments		28,825
Amortized Cost
Amortized cost	29,060	$ 28,891
Fair Value
Available-for-sale Securities	$ 29,018