Fair Value Measurement (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Jun. 30, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mutual funds	$ 9,042	$ 12,807
Mutual funds, fair value	9,042	12,807
Held-to-maturity securities, maturities less than 1 year	1,506	353
Held-to-maturity securities, maturities less than 1 year, fair value	1,504	352
Held-to-maturity securities, remaining maturities from 1-3 years	1,638	3,160
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	1,633	3,166
Held-to-maturity securities, maturities from 1-90 days	0	2,243
Held-to-maturity securities, maturities from 1-90 days, fair value	0	2,244
Held-to-maturity securities, maturities from 91-360 days	250	1,699
Held-to-maturity securities, maturities from 91-360 days, fair value	251	1,703
Held-to-maturity securities, maturities over 360 days	548	1,048
Held-to-maturity securities, maturities over 360 days, fair value	547	1,050
Investments	12,984	21,310
Investments, fair value	12,977	21,322
Fair Value Inputs Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Mutual funds, fair value	9,042	12,807
Investments, fair value	9,042	12,807
Fair Value Inputs Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Held-to-maturity securities, maturities less than 1 year, fair value	1,504	352
Held-to-maturity securities, remaining maturities from 1-3 years, fair value	1,633	3,166
Held-to-maturity securities, maturities from 1-90 days, fair value	0	2,244
Held-to-maturity securities, maturities from 91-360 days, fair value	251	1,703
Held-to-maturity securities, maturities over 360 days, fair value	547	1,050
Investments, fair value	$ 3,935	$ 8,515