| Business Combination  - Purchase Price Allocation (Details) - USD ($) $ in Thousands | Jun. 30, 2017 | Jun. 09, 2017 | Jun. 30, 2016 | Jun. 30, 2015 | 
|---|---|---|---|---|
| Preliminary Purchase Price Allocation | ||||
| Goodwill | $ 349,526 | $ 335,177 | $ 335,263 | |
| Privately-held Design and Manufacturing Company | ||||
| Preliminary Purchase Price Allocation | ||||
| Intangible assets | $ 17,660 | |||
| Goodwill | 14,280 | |||
| Assets acquired (including cash and marketable securities of $3.2 million) | 6,294 | |||
| Liabilities assumed | (1,334) | |||
| Fair value of net assets acquired | 36,900 | |||
| Cash and marketable securities | $ 3,200 | 
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- Definition Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Assets, Other Than Goodwill And Intangible Assets No definition available. 
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- Definition Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Cash and Equivalents, And Current Assets, Marketable Securities No definition available. 
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- Definition Amount of intangible assets, excluding goodwill, acquired at the acquisition date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount of liabilities assumed at the acquisition date. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- References No definition available. 
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- Definition Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. Reference 1: http://www.xbrl.org/2003/role/presentationRef 
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- Details 
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