Fair Value - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Jun. 30, 2017
Assets
Total available for sale debt securities	$ 9,958	$ 1,906
Fair Value, Measurements, Recurring [Member]
Assets
Money market funds (cash and cash equivalents)	100	593
Total available for sale debt securities	9,958	1,906
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member]
Assets
Short-term derivative interest rate swap	169
Long-term derivative interest rate swap	1,830
Fair Value, Measurements, Recurring [Member] | U.S. Corporate [Member]
Assets
Total available for sale debt securities	3,489	1,906
Fair Value, Measurements, Recurring [Member] | Government - U.S. [Member]
Assets
Total available for sale debt securities	6,469
Fair Value, Measurements, Recurring [Member] | Level 1 [Member]
Assets
Money market funds (cash and cash equivalents)	100	593
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Assets
Total available for sale debt securities	9,958	1,906
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Interest Rate Swap [Member]
Assets
Short-term derivative interest rate swap	169
Long-term derivative interest rate swap	1,830
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | U.S. Corporate [Member]
Assets
Total available for sale debt securities	3,489	$ 1,906
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Government - U.S. [Member]
Assets
Total available for sale debt securities	$ 6,469