Fair Value Measurements - Assets Carried at Fair Value Measured on Recurring Basis (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Jun. 30, 2016
Assets:
Cash equivalents	$ 13,521	$ 13,856
Marketable securities	0	13,679
Cash equivalents and marketable securities	13,521	27,535
Corporate Bonds [Member]
Assets:
Marketable securities		5,997
Commercial Paper [Member]
Assets:
Marketable securities		7,682
Quoted Prices in Active Markets (Level 1) [Member]
Assets:
Cash equivalents	13,521	12,957
Cash equivalents and marketable securities	13,521	17,553
Quoted Prices in Active Markets (Level 1) [Member] \| Corporate Bonds [Member]
Assets:
Marketable securities		4,596
Quoted Prices in Active Markets (Level 1) [Member] \| Commercial Paper [Member]
Assets:
Marketable securities		0
Significant Other Observable Inputs (Level 2) [Member]
Assets:
Cash equivalents	0	899
Cash equivalents and marketable securities	0	9,982
Significant Other Observable Inputs (Level 2) [Member] \| Corporate Bonds [Member]
Assets:
Marketable securities		1,401
Significant Other Observable Inputs (Level 2) [Member] \| Commercial Paper [Member]
Assets:
Marketable securities		7,682
Significant Unobservable Inputs (Level 3) [Member]
Assets:
Cash equivalents	0	0
Cash equivalents and marketable securities	$ 0	0
Significant Unobservable Inputs (Level 3) [Member] \| Corporate Bonds [Member]
Assets:
Marketable securities		0
Significant Unobservable Inputs (Level 3) [Member] \| Commercial Paper [Member]
Assets:
Marketable securities		$ 0

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- Definition

This element represents the aggregate of the assets reported on the balance sheet at period end measured at fair value on a recurring basis by the entity. This element is intended to be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements.

+ References

No definition available.

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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=75030427&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26626-111562

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- Definition

Amount of short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.1)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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