Restructuring Charges - Changes in restructuring liabilities - (Details) - USD ($) $ in Thousands	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Reconciliation of the changes in restructuring liabilities
Restructuring Charges	$ 7,061	$ 7,168	$ 7,166
Cody Restructuring Plan
Reconciliation of the changes in restructuring liabilities
Restructuring Charges	3,092
Ending balance for the period	3,092
Cody Restructuring Plan \| Employee separation costs
Reconciliation of the changes in restructuring liabilities
Restructuring Charges	3,092
Ending balance for the period	3,092
2016 Restructuring Plan
Reconciliation of the changes in restructuring liabilities
Beginning balance for the period	5,431	4,130
Restructuring Charges	3,969	7,168
Payments	(5,786)	(5,867)
Ending balance for the period	3,614	5,431	4,130
2016 Restructuring Plan \| Employee separation costs
Reconciliation of the changes in restructuring liabilities
Beginning balance for the period	5,431	3,833
Restructuring Charges	246	3,486
Payments	(2,063)	(1,888)
Ending balance for the period	3,614	5,431	3,833
2016 Restructuring Plan \| Contract termination costs
Reconciliation of the changes in restructuring liabilities
Beginning balance for the period		297
Payments		(297)
Ending balance for the period			$ 297
2016 Restructuring Plan \| Facility closure costs
Reconciliation of the changes in restructuring liabilities
Restructuring Charges	3,723	3,682
Payments	$ (3,723)	$ (3,682)

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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