Defined Benefit Pension Obligation - Amounts Recognized (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Jun. 30, 2017
Amounts recognized within the consolidated balance sheets:
Assets	$ 378,727	$ 406,464
Defined benefit pension plan
Amounts recognized within the consolidated balance sheets:
Long-term other liabilities	(2,062)	(2,686)
Net amount recognized	(2,062)	(2,686)
Amounts recognized in accumulated other comprehensive loss (before tax)
Net loss	(1,117)	(2,066)
Prior service cost	973	949
Accumulated other comprehensive loss	(144)	(1,117)
Accumulated benefit obligations in excess of fair value of plan assets:
Projected benefit obligation	14,254	13,979
Accumulated benefit obligation	12,413	11,293
Fair value of plan assets	$ 12,192	$ 11,293

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount, before 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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Amount, before tax, of accumulated other comprehensive (income) loss for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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Amount of asset (liability), recognized in statement of financial position, for defined benefit pension and other postretirement plans.

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Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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