Summary of Significant Accounting Policies - Accumulated Other Comprehensive Income (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Operating Leases, Future Minimum Payments Due	$ 69,630,000
Accumulated other comprehensive income adjustment for foreign currency	(232,000)	$ (137,000)	$ (93,000)
Accumulated other comprehensive income adjustment for pension plans	(2,350,000)	$ 354,000	$ 220,000
Accumulated other comprehensive income, available-for-sale securities gains (losses)	$ 0			$ 0

Accumulated unrealized gain (loss), after tax, on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Accumulated adjustment, net of tax, that results from the process of translating subsidiary financial statements and foreign equity investments into the reporting currency from the functional currency of the reporting entity, net of reclassification of realized foreign currency translation gains or losses.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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