Marketable Securities - Maturities of Debt Securities Classified as Available-for-Sale (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016
Marketable Securities
Fair Value, Due within one year	$ 89,477
Fair Value, Due after one year through five years	22,031
Fair Value	111,508	$ 37,424
Net Carrying Amount, Due within one year	89,728
Net Carrying Amount, Due after one year through five years	22,149
Net Carrying Amount	$ 111,877