Estimated Fair Value of Financial Instruments (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Jun. 30, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 47,436	$ 96,304
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	10,012	10,138
U.S. Treasury Bonds [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	5,065	13,389
Certificates of Deposits [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	3,003	6,004
U.S. Government Sponsored Agencies [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	14,342	40,715
Corporate Debt Securities [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	15,014	26,058
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	47,436	96,304
Level 1 [Member] | Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	10,012	10,138
Level 1 [Member] | U.S. Treasury Bonds [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	5,065	13,389
Level 1 [Member] | Certificates of Deposits [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	3,003	6,004
Level 1 [Member] | U.S. Government Sponsored Agencies [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	14,342	40,715
Level 1 [Member] | Corporate Debt Securities [Member] | Marketable Securities [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Financial assets	$ 15,014	$ 26,058