Marketable Securities - Maturity Schedule (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018
Investments, Debt and Equity Securities [Abstract]
Fair value, due within one year		$ 21,745
Fair value, due after one year through five years		5,000
Fair Value		26,745
Net carrying amount, due within one year		21,860
Net carrying amount, due after one year through five years	$ 4,954	5,009
Net Carrying Amount		$ 26,869